Villain in this hand is 47.5/0.7/1.77 over 140 hands. I'd prefer that you guys focus on evaluating this hand, rather than the possibility of future hands vs same villain.

On the river, we still have decent stacks left, and I intend to fold to a push/reraise.

Party Poker No-Limit Hold'em, $ BB (9 handed) from (Format: Bet The Pot)

SB ($104.72)
BB ($52.05)
UTG ($52.89)
UTG+1 ($100.88)
MP1 ($40.95)
MP2 ($8)
MP3 ($37.20)
CO ($50)
Hero ($52.04)

Preflop: Hero is Button with , . SB posts a blind of $0.25. CO posts a blind of $0.50.
3 folds, MP2 calls $0.50, MP3 calls $0.50, CO (poster) checks, Hero raises to $3.5, SB (poster) calls $3.25, 1 fold, MP2 folds, MP3 calls $3, CO folds.

Flop: ($12) , , (3 players)
SB checks, MP3 bets $3, Hero raises to $9, SB folds, MP3 calls $6.

Turn: ($30) (2 players)
MP3 checks, Hero checks.

River: ($30) (2 players)
MP3 bets $3, Hero raises to $8...

wtf is with the river play? raise to $8? in a $30 pot? either make a real raise or just call.

PF call
flop check/fold
turn check/fold
river call

If you want to steal this pot on the flop, then you need to raise to atleast 12.

However, that's not the big mistake here, your river play is. THat raise on the river is really bad. You have reopened the betting with a marginal hand with showdown value. Why? To make an extra $5 those times when he doesn't reraise you off your hand? Ugh.

Call the river and see if you win. If you want to raise this river (which I wouldn't recommend) you need to raise to $20-30, not $8.