($10.10 Stars) Top Pair with K5, 3-flush on the river

[RoyalLance]

We are in the money and my two opponents are fish-bad-mouthing fish duo. I had to leave it to myself to pick up hand and take out the fourth guy while the two fish were arguing on which of the two are the bigger fish.

PokerStars No-Limit Hold'em Tourney, Big Blind is t200 (3 handed) converter

Button (t2890)
Hero (t5110)
BB (t5500)

Preflop: Hero is SB with K[img]/images/graemlins/diamond.gif[/img], 2[img]/images/graemlins/diamond.gif[/img].
Button calls t200, <font color="#CC3333">Hero raises to t500</font>, BB calls t300, Button calls t300.

Flop: (t1350) 9[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/spade.gif[/img], T[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets t800</font>, BB calls t800, Button folds.

Turn: (t2950) Q[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero ....

Do I give up the pot here or should I just get my money in and hope for the best?