$10/180, boat against suspected trips.. river value?

[ChipSpeak]

PokerStars No-Limit Hold'em Tourney, Big Blind is t20 (9 handed) internettexasholdem.com

Villain (MP1) has shown he's very weak... already shown A rag limped in ep.

What's your river bet?
Comments on all streets welcome.

Button (t920)
Hero (t1440)
BB (t1460)
UTG (t1540)
UTG+1 (t1860)
MP1 (t1350)
MP2 (t1660)
MP3 (t1400)
CO (t1870)

Preflop: Hero is SB with 3[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/club.gif[/img].
<font color="#666666">2 folds</font>, MP1 calls t20, <font color="#666666">3 folds</font>, Button calls t20, Hero completes, BB checks.

Flop: (t80) 3[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">Hero bets t60</font>, BB calls t60, MP1 calls t60, Button calls t60.

Turn: (t320) A[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">Hero bets t200</font>, BB folds, MP1 calls t200, Button folds.

I really thought someone would come over this bet... too small?

River: (t720) 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero?</font>