Your hand kind of looks like AK and I'm not expecting any reg to try and bluff you off. We should expect them bet out with all sets on the turn, so I discount all sets from their river value range. Kx just calls the river, as much as I hate to give people narrow ranges, if we assume they are a reg I'm expecting to see a flush here quite often. We could make stronger arguments for calling if we held a spade in our hand.
Interested in what others have to say.