how about an old (pun intended) manual typewriter.Become a priest and sell indulgences.
(okay, so you may too early by a century or two…But I bet that if anybody had thought of selling indulgences as early as 1000 A.D, they would have sold just as well as they did in the1300’s.)
I don’t think that seeds are the best things for a temporal tourist to take along. First you have to plant the things, then wait for them to grow, then show the skeptical locals just what it’s good for. If you plan to LIVE back then, yes, seeds are great. I don’t think that they’d be good short term trade goods, though.
Same thing with dyes. Sure, you could show His Lordship the glories of neon orange, and he might be impressed, but would he like it? Would he want to wear it, or sell it? And, more importantly, would he believe you, the stranger, will sell him more of the same, or will you try to scam him? There’s a limit as to how much bulk and weight the traveler can carry, and I think that other goods would be more convenient and worth more.
I have to say that taking along good pins and needles would be a wonderful idea. Very cheap to purchase now, and very expensive to purchase then. What’s more, modern pins and needles are vastly superior in quality.
Carry a Christian Bible at all times. Be prepared to quote from it, to prevent being hanged as a witch. It might be a good idea to claim to be a monk or cleric or layman from a distant land, traveling on a pilgrimage.
Oh, and that brings up another point. If you’re female, you’d probably better disguise yourself as a beardless youth, get yourself on some sort of hormones that suppress your periods, and try to avoid nude situations in general.
Except this might get you arrested. There were periods when unauthorized possession of a Bible (especially an unauthorized translation) was illegal. It was considered evidence that you were probably a heretic who was defying church authority.
Cannabis was native to the Old World.
Assuming you have no moral objections, hard drugs would give you very high “bang per pound”. Introduce one or two key nobles to cocaine or heroin, and the world is your oyster. Far more effective than sugaring their tea. 
One of those little laser pointers. Endless fun freaking the natives out with that little dot of light. But be sure to project it surreptitiously, or else you could find yourself burned at the stake.
Bring an encyclopedia and an orb…make a living as a prophet / oracle.
That’s why I said to claim to be a cleric or monk or layman on pilgrimage. Being on a pilgrimage was a good way to lay claim to moral righteousness, it explained most oddities, and a pilgrim was generally considered to be a person with his heart in the right place.
Getting the right translation is something I leave as an exercise for the time traveler. However, getting such a translation done in plastic pages, in a very durable binding, and then claiming that it’s a miracle or artifact…that might be worth doing.
As I said above, a backpack full of those little REI keychain compasses would be invaluable. Those, with a bunch of reliable windable watches would finance not just a vacation, but an empire. The hard part would be keeping anyone from just beating you up and taking them.
That’s where the pocket Uzi would come in handy.
Until two seconds later when the magazine it empty and you’re left facing a bunch of people with axes and pitchforks. Not a particularly accurate or controllable weapon.
Stranger
Nah, just one very short burst and the others are all running for the hills like the devil is after them.
I feel like a revolver would be more practical. You might even be able to reload it if you brought along the proper equipment and you did some research on how to make decent black powder.
More likely until someone takes a potshot from behind with bow and arrow or waits for you to fall asleep. A firearm is not a protective shield, and if it makes you feel ten feet tall and invincible you are better off without it.
The reloading press and dies alone would eat up the o.p.'s weight budget. And how much time are you going to spend looking for sources of sulphur and saltpeter and purifying them into a usable form? Then there are primers; I doubt you’d be able to make mercury fulminate, tetrazine, or lead azine in such primitive conditions even if you could procure the necessary chemical substances. And then you’ve have to make the cup and anvil for the primer, and of course cast the bullets. On the whole, you’re better off avoiding the kind of trouble that would require you to discharge a firearm to begin with.
Stranger
Thank you, Robert Heinlein. 
Seriously, I didn’t know exactly what to expect for reloading materials. Ignorance fought. But given that a stranger with some wealth who doesn’t speak the language well is not the sort who can easily avoid trouble, it might be worth carrying.
Only as a last resort; not something to spend the majority of your weight budget on. And I would pick a modern, compact, reliable, contamination-resistant service pistol like the Glock, Sig-Sauer, or HK USP over an easily damaged and contamination-prone revolver.
Stranger
I’d go with a high capacity, polymer framed automatic and load it with some top shelf ammo. An pair of extra magazines and you’re good to go. Depending on the gun and cartridge combination, that should give you anywhere from 37 to 60 shots at your disposal. That should be plenty (and then some) since, AFAIK, the purpose of this time travel vacation is not to go back and kill a bunch of primitive screwheads.
A lot of the weapons from the time period were piercing or cutting weapons, so I might also take the trouble to have clothing made with fibers that are resistant to cutting. A jacket made from such, at least.
In any case, if all you want is a fight then that is available in the here and now. There’s no need for time travel. So I’d be at great pains to just avoid trouble as much as possible.
You can still get a Vulgate (Latin) Bible these days. Although you’d probably have to get it on special order, and it might cost a few hundred dollars. But, hey, you can put it on your credit card, right? It’s not as if they’re going to be able to find you to collect your bill.
Pro tip for the time traveler so inclined: Learn enough medieval Latin to get by (yes, its pronunciation is not perfectly known, but it’s known enough to likely be reasonably understood). Take an illustrated Vulgate Bible to the biggest monastery you can find. Present yourself to the Top Bloke and gift him the Bible. If he asks questions about the Bible, tell him it’s a gift from God and the finest scribes and craftsmen of a great land, blah blah blah. Tell him you need a place to stay. Voila, a base of operations with unlimited food and beer.
Now when you need to leave to sell those pounds of spices you brought along, make sure you come back with presents.
You could get one delivered by April 27 from Amazon for $52.26. Just search for “vulgate bible” on Amazon.