if you didnt get any you still have a chance..... there are more than 14 of these out there
The only thing I can add is the 1931 W517 set uses many of the same images as the "1925-31 PC Back Exhibits" (aka "Set 81", PC792-2), except they glued a number to the front (which then fell off on the 2 numberless variations PWaner, Vance)
here is a link to an auction for some of the W517 original art (very similar to the ones on eBay today)
http://www.lelands.com/Auction/Aucti...iginal-Art-(3)
Adam W probably knows, but I think W517s and the minis may have been made by the Exhibit Supply Co., (I think I read something about that)
Maybe all these "original arts" came from same find ??? I just did a quick search (Im at McD and got good internet speed for once
) and see on Adams Exhibit page he shows one of these Exhibit original arts... so he (and obviously "orioleal123") knew about these for a while