Yeah... you're going broke on this one, as there's a string of overpairs that he could play the same way. I would prolly 3-bet or push over the flop, esp with the draw on the board at these levels. If it's a set or some kinda flopped two pair (altho connectors might be a bit less likely for a maybe tight player opening under the gun...) then meh... nh and move on to the next. You can't run the risk of seeing sets everywhere when you get played back at at these levels. People will get aggressive with a lot worse hands than that.