You could see if you can find any with an in-house specialist and then e-mail them together with a couple of good quality photos, saying that you are interested in selling. They won't be able to tell from your e-mail where you live. If it turns out to be at all valuable then you'd probably want to sell it through an Auction House that runs specialist auctions.
I've never ever not had a reply from a local Auction House with some info and a guide price. Whereas, I haven't been too lucky with places like Sotherby's .. as became apparent on a thread a while back.
Good luck!