… in which Humphrey Bogart plays Captain Queeg, in command of a WW2 minesweeper, who goes a bit “round the bend”, one symbol of which is his habit of rolling a couple of ball bearings in his hand.
A bottle of the best rum you can get: rum, sodomy and the lash and all that!
Of course a critical thing is the question of budget. For really important things - like getting such a position, I tend to have a few rules that are irrespective of budget. Whatever it is should be durable not consumable, it should be the best of its kind, it should not be breakable.
Clearly a nautical theme is good. Something that could be displayed in his cabin, or used in everyday life really good.
There is much to be said for high end pens. POTUS gets a Parker pen. Parker make a big deal about that. This took my fancy on the shipslocker site linked to above:
Of the half hulls they have, this is the only US defender. The others are British challengers. Ranger of course saw off the challenges.
If you have a used bookstore in the area checkout some of the older books.
I found my great grandfather, who was born in the 20s and a farmer all his life, a copy ofa USDA report from his birth year. It was this big thick book and hecka interesting. He really liked it.
Maybe you could find him some nautical writings from a bygone era.
A signed photo of Captain Joseph Hazelwood.
The first thing I thought of was a movie where the depised skipper of the navy ship is torrmented by a crew member who puts ball bearings in the over head light fixture in his cabin.
This must have been a riff on the Caine Mutiny but I Google isn’t helping.
Anyone?
How about an antique copy of Bowditch?
There are some nice sextants on Ebay at present. (Ignoring the obvious copies ;))
That’s Mister Roberts, with Jack Lemmon torturing James Cagney.
ETA: and they were marbles. I can just hear Lemmon’s delight when he says marbles! 
And be sure the parrot is only “sleeping”
If his ship has a namesake you cannot go wrong with that. An example, one Captain of the USS Ranger had a model of John Paul Jones’ USS Ranger.