Couldn't find anything on J&G.
Cash America Pawn runs an online gun auction. The Maks are going for a pretty good price. Here's the link:
Auction Arms - All Categories
I paid $325 for mine - the Russian civilan model with adjustable rear site - at a local gun show. Only one there I saw. I think the days of buying a decent surplus Mak for $100 - $150 are gone however.
Good luck.