I don’t have any numbers or positive things to report yet, but I’ve just started to promote Betsson.com, which I kinda like as a player (it’s a betting exchange).
AffiliateLounge also has a Czech language casino ( I can’t remember which one) which would work well as my friends from that part of the world tell me the Czechs like to gamble. All you need is a high quality translator. I’ve not promoted them this way yet, but the lack of competition tells me it’s a winner.