TPTK vs a probable draw and a three bet

I've seen all kinds of hands shown down in this type of situation over the last couple of weeks. These ultra passives have been driving me nuts when I flop well like this hand. Does anyone just try to get to showdown as cheap as possible? Could a flop fold be better?

Button 55/6/1 (55 hands)
SB 60/1/1 (210 hands)

Party Poker 1/2 Hold'em (6 max, 6 handed) FTR converter on zerodivide.cx

Preflop: Hero is CO with T[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/heart.gif[/img].
2 folds</font>, Hero raises</font>, Button 3-bets</font>, SB calls, 1 fold</font>, Hero calls.

Flop: (10 SB) 4[img]/images/graemlins/diamond.gif[/img], T[img]/images/graemlins/club.gif[/img], 3[img]/images/graemlins/club.gif[/img] (3 players)</font>
SB checks, Hero bets</font>, Button raises</font>, SB calls, Hero 3-bets</font>, Button calls, SB calls.

Turn: (9.50 BB) 6[img]/images/graemlins/heart.gif[/img] (3 players)</font>
SB checks, Hero bets</font>, Button calls, SB calls.

[Spartan1983]

SB could have anything with his stats. button doesn't raise much, so his 3 bet is a little worrisome. But he doesn't cap the flop. I think you have to bet the turn, with TPTK. Depending on the river card, I might consider check/call. Looks like one of them is setting on the flush draw.