open strt draw play?

[Draidin]

I have just over 7 BBs and have NOT been active at all. Two PF raises and some flop bets for me and no showdowns. Button [BTN] bets when they have it. Flop gives me open-ender.
How to play this: ?

Poker Stars, $5 + $0.50 NL Hold'em Tournament, 50/100 Blinds, 5 Players
LeggoPoker.com - Hand History Converter

CO: 2,880
BTN: 1,600
SB: 3,945
<font color="blue">DRAIDIN</font> (BB): 775
UTG: 4,300

Pre-Flop: (150) 3[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/diamond.gif[/img] dealt to <font color="blue">DRAIDIN</font> (BB)
2 folds, BTN calls 100, SB calls 50, <font color="blue">DRAIDIN</font> checks

Flop: (300) K[img]/images/graemlins/club.gif[/img] 5[img]/images/graemlins/diamond.gif[/img] 6[img]/images/graemlins/diamond.gif[/img] (3 Players)
SB checks, <font color="blue">DRAIDIN</font> checks, <font color="red">BTN bets 200</font>, SB folds

<font color="blue">DRAIDIN</font> - ?