I think I fold this one on the flop to the 3-bet CR by the weak-tight villian. I mean what else could he have here besides the flush (maybe a set, but that's still very bad news for you)? Plus if you hit another club, what makes you think that mr. weak-tightie will pay you off with a badly counterfeited flush or a meaningless set? What if the turn blanks and the board pairs a club? But I think if you wanted to make a move here, the turn would be the place to do it, rather than the river. It would probably buy you a free showdown as well if that means anything.