This may be somewhat off topic but part of this might be useful.
Some years ago I decided to send out antique Victorian Christmas postcards to close family and friends. They were all in unused condition and were all well over 100 years old but none were particularly rare. They were valued mostly around $10 which I thought wasn't a lot. I know people who spend nearly that much per person on fancy Christmas Cards that go in envelopes. But here is the twist. I found old unused postage stamps from the years the postcards were printed or in some cases approximate years. They were of course in the correct a amount for post cards but just all stamps that were issued 110 to 120 years ago. Yes I paid a lot more for them than I would for stamps issued this year but none were high end stamps. None had Scott values over $10 and most had minor defects that would not be noticed by the recipient as none were stamp collectors but I thought they would be a nice touch. For a bonus our post office at the time was using special Christmas cancellations in an attractive Victorian style. Since I belonged to the stamp club that met weekly at that post office where our philatelic clerk was a member (and vice president) I had heads up advance notice of that special cancellation which gave me the idea for sending out the Victorian Christmas postcards with the stamps from the period.
My point is you can often find an appropriate vintage stamp on eBay
or elsewhere that fits any theme including gag or joke gifts or practical jokes.