Not to take anything away from this board, but there's another discussion board with a very strong following among US FDC collectors, including many of the officers of the AFDCS. (In fact, the founder of that board is the current president of the AFDCS.)
I would post there:
http://forums.delphiforums.com/stamps/messageseither in the "First Day Covers" folder or in the "Buy/Sell/Trade" folder.
I'm sure someone would have an interest, or know who the specialized collectors of that issue or that kind of ephemera are.
Like here, you do need to register on that site (Delphi) in order to post, but it's relatively simple. Make sure you don't pay for anything. Just the simple Delphi membership/registration is all you need. Someone there is also likely to be able to help you with the images, once you make your post about the material. Unlike here and some other boards, you don't start out as a probationary participant.
I'll look for your post over there!
-- Dave