You could use the second and third pictures on this page. Just print them out double sided.
From what I can find, that’s right – the Bank of England didn’t issue notes in denominations lower than £5 till 1928.
As you also say, they were very large in comparison to modern currency – it occurs to me that realistic reproductions of 1922 English banknotes may not even be immediately identifiable as money to a modern American audience.
Ah, hang on: it seems there were lower denominations.
A fast, simplistic way to get something that looks like pound notes, although it’s going to cost you a lilttle: Go to the nearest international airport or wherever the nearest place that has a currency exchange booth. Exchange $200 for whatever they will give you in British currency. This will be a little more than a hundred pounds, plenty to be convincing as the amount of money that would pay for a vacation in 1922. Use this during the run of the play. Yeah, it’s modern currency and not quite the same as the money of the period, but what are you worried about? Will someone in the audience complain that he can see that you’re not using British currency of the correct time period? After the run of the play is finished, go back to the currency exchange booth and change it back to American money. You will lose $30 or so on the two exchanges, but isn’t this easier than worrying about finding something else that looks right?
At that distance, you could just use money-sized pieces clipped out of a newspaper’s stock market pages.
If anyone in the audience is going to notice that it’s not real money, they’re not paying attention to the play itself.
Thirty dollars for one prop? One that could be faked in Photoshop?
Damn, I wish our local theater groups had the funding to be that profligate.
The OP wants something that kinda sorta resembles real currency. Thus, this plan would only work in Canada. duck & run
The current sterling notes (the lowest denominations are 5, 10 and 20 pounds) look nothing like sterling notes looked like in 1922. I’d say the best solution is to get some pictures of 5 pound notes from around the 1920s, photocopy them, and trim them to something like the right size. From a distance, they’ll look pretty much the same as the real thing. It’s the cheapest solution, and probably the best (since, even with an unlimited budget, you would not want to be using real 5 pound notes from the period).
Hey, at least our money’s pretty. :mad:
Question: In the US, anything that ever was legal tender still is legal tender for its face value, so if I found a stash of cash in my backyard burried in 1800, I could still legally spend it for face value (though I would probably have a hard time getting anyone to recognize it, and I could probably get considerably more from a collector). But I understand that the US is somewhat atypical in this regard. Are bills from the 1920s still legal tender in the UK? And if not, would an exact replica be considered a counterfeit?
No, they’re not valid currency (‘legal tender’ is something different in the UK, and misuse of the term is one of my pet peeves 
) Theoretically, all notes will still be exchanged for face value by the Bank of England.
I’m not sure whether making a copy of a banknote is itself considered counterfeiting, or whether it has to be with the intent to decieve or to defraud. If the latter, then copying old notes would only be counterfeiting if you intended to take them to the Old Lady and cash them in for £5 a pop. However, they’re still copyright - Crown Copyright does not expire.