Is this river bet worth making?

This is from a Party 5+1 Rebuy, no reads on this guy.

Party Poker No-Limit Hold'em Tourney, Big Blind is t200 (10 handed) converter

BB (t10629)
UTG (t2408)
UTG+1 (t13530)
Hero (t7535)
MP1 (t5700)
MP2 (t1240)
MP3 (t8185)
CO (t5095)
Button (t11510)
SB (t14205)

Preflop: Hero is UTG+2 with Q[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">2 folds</font>, <font color="#CC3333">Hero raises to t600</font>, <font color="#666666">6 folds</font>, BB calls t400.

Flop: (t1300) 2[img]/images/graemlins/diamond.gif[/img], 9[img]/images/graemlins/diamond.gif[/img], 2[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, <font color="#CC3333">Hero bets t700</font>, BB calls t700.

Turn: (t2700) J[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, Hero checks.

River: (t2700) K[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, <font color="#CC3333">Hero bets t1200</font>...

My thinking here is that Villain may well have a medium pocket pair that looked good on the flop, but that became less and less appealing following the J turn and K river. When I bet again on the river, I represent something like AK, and hopefully can get him to drop a lower pair. Will I get away with this enough to be profitable, or should I just check it down and hope he was on a flush draw?