33 isnt a concern as well, I think the only hands you are worried about is 4 6 and 77. BB could easiy be holding 73 or an outside shot of 75. So your only beat two ways. Set over set happens however unlikley. Calling the third raise will should set alarms off in the BB head if he doesnt have 4 6 or 7 7. Call the flop, and I actucally like a check behind on the turn. It will induce a bet from a worse hand on the river or simply create a cheper showdown without going broke. And if the board pairs im sure their is only one soloution that comes to mind.