Weird river spot, what's my best line?

[pp262]

600NL 6handed

Villain has been playing fairly loose and agressive preflop. He bought in for ~60BB and stacked me in a rrd pot when I cr'd a 944ss flop and lost to his AKss.
Other than that he has mostly been playing small pots and he doesn't seem to be continuation betting too often.
I have been playing 20/17/3 ish.
BB is fairly passive so I elect to call preflop.
Flop and turn are fairly standard I think, not much sense in 3betting the turn.

What's your river line?

SB (Hero) $706.90
BB $1,540.05
UTG $791.65
MP $603.00
CO (Villain) $610.00
BN $595.80

Dealt to Hero A [img]/images/graemlins/spade.gif[/img] 9 [img]/images/graemlins/spade.gif[/img]

2 folds, CO raises to $21, 1 fold, Hero calls $18, 1 fold

Flop: 8 [img]/images/graemlins/diamond.gif[/img] A [img]/images/graemlins/club.gif[/img] 7 [img]/images/graemlins/spade.gif[/img] ($48)
Hero checks, CO checks

Turn: 6 [img]/images/graemlins/spade.gif[/img] ($48)
Hero bets $35, CO raises to $100, Hero calls $65

River: 5 [img]/images/graemlins/club.gif[/img]
Hero....