2nd nut gapstraight vs fishy limper - go broke here?

[ArgusSpets]

Villain is considered as fishy, no real history or hands but stack, action etc:

PokerStars No-Limit Hold'em, $4 BB (6 handed) by Hand Converter CG

saw flop|<font color="#C00000">saw showdown</font>

UTG ($308.50)
MP ($489.50)
CO ($212.40)
<font color="#C00000">Button ($280.55)</font>
SB ($444.90)
<font color="#C00000">Hero ($561.40)</font>

Preflop: Hero is BB with 8[img]/images/graemlins/spade.gif[/img], T[img]/images/graemlins/club.gif[/img].
UTG calls $4, MP folds, CO folds, Button calls $4, SB completes, Hero checks.

Flop: ($16) J[img]/images/graemlins/diamond.gif[/img], Q[img]/images/graemlins/club.gif[/img], 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, <font color="#CC3333">Hero bets $12</font>, UTG folds, <font color="#CC3333">Button raises to $24</font>, SB folds, <font color="#CC3333">Hero raises to $68</font>, <font color="#CC3333">Button raises to $276.55</font>,

The small 3bet was because I wasnt really sure if I will stack down here vs this guy, who could possible have TK. If I reraise larger Im def. calling.

Thoughts please.