[SH] nl50 anonomous vbet River?

I justed started at this table so all Villains are unknown

one read is that Player 3 isn't full stacked.
Player 2 is probably a reg.

So on the flop i still think the reg can have some TP, 2P, sets to keep the "fish" in. The fish probably ch/r 3way. So my main concern is the reg atm.

Turn: isn't the best since OESD completes. I still have to bet here vs TP, Pair + draws. The reg will raise his sets now for actionkillers on river.

bet/fold turn is ok? what sizing?

River: easy vbet? sizing? villain has 26.6 behind in a 28 pot. Can i bet half pot and fold? or just jam? or .......?

CO: $37.96 (94.9 bb)
BTN: $57.67 (144.2 bb)
SB: $38.80 (97 bb)
BB: $70.75 (176.9 bb)
Hero (UTG): $42.57 (106.4 bb)
MP: $105.97 (264.9 bb)

Preflop: Hero is UTG with A A
Hero raises to $1.40, 2 folds, BTN calls $1.40, SB calls $1.20, BB folds

Flop: ($4.60) Q 7 K (3 players)
SB checks, Hero bets $3, BTN calls $3, SB calls $3

Turn: ($13.60) 9 (3 players)
SB checks, Hero bets $7.20, BTN folds, SB calls $7.20

River: ($28) Q (2 players)
SB checks, Hero?