villain is a 24/10 75 hands opened 5% in EP so far , no data on fold to flop/turn CB

question , is it ok to bet this river. secondly , which cards would you possible barrel on the river that didn't improve my hand. Can i ever barrel river unimproved? ty

No-Limit Hold'em, $0.05 BB (9 handed) - Hold'em Manager Converter Tool from FlopTurnRiver.com

MP2 ($2.44)
MP3 ($3.34)
CO ($4)
Button ($3.93)
SB ($16.70)
Hero (BB) ($5.42)
UTG ($5.19)
UTG+1 ($12.08)
MP1 ($2.16)

Preflop: Hero is BB with A, K
UTG bets $0.15, 7 folds, Hero calls $0.10

Flop: ($0.32) 8, 3, 3 (2 players)
Hero checks, UTG bets $0.20, Hero calls $0.20

Turn: ($0.72) 8 (2 players)
Hero checks, UTG bets $0.45, Hero raises $1.25, UTG calls $0.80

River: ($3.22) A (2 players)
Hero bets $1.70, 1 fold

Total pot: $3.22

Results below:
Hero had A, K (two pair, Aces and eights).
Outcome: Hero won $4.77