I'd like some comments on my bet-sizing with this hand. I'd only played a few hands with this guy so obvious reads (I have been working hard on keeping notes and gaining reads on players). His play suggests to me he likely has an A or a busted draw. Is potting the river a good idea?

PokerStars No-Limit Hold'em, $0.10 BB (8 handed) - Poker-Stars Converter Tool from FlopTurnRiver.com

Button ($5.60)
SB ($1.90)
BB ($4.60)
UTG ($2)
UTG+1 ($10.65)
MP1 ($3.10)
MP2 ($10.90)
Hero (CO) ($10)

Preflop: Hero is CO with 8, 8
3 folds, MP2 calls $0.10, Hero calls $0.10, 2 folds, BB checks

Flop: ($0.35) 8, A, 9 (3 players)
BB checks, MP2 bets $0.20, Hero raises to $0.60, 1 fold, MP2 calls $0.40

Turn: ($1.55) 2 (2 players)
MP2 checks, Hero bets $1.20, MP2 calls $1.20

River: ($3.95) A (2 players)
MP2 checks, Hero bets $4, 1 fold

Total pot: $3.95 | Rake: $0.15