Looks like your poster had some action going, with 38 bids.
Not everything he sells is fake. He's one of those that has the good mixed in with the bad. (And im not condoning buying from him or not, just stating what I have heard from other collectors).
From the description and the fact he says it was to be a festival that never came about, there is always the chance that it could be the real deal. The size is right, according to his description. And perhaps the distributor had some local printer run some of these off.
It could be bogus, but considering it was for some film festival in 1982, I'd dig a little more before tossing it off as a fake (and it certainly could be phony but i think a bit more
might be needed).
Maybe you got lucky!