it's like 8/10 from the money in the 125k gtd. villain is a sometimes spewy but good mid/high stakes reg i just got moved to this table 2 hands before so no recent history.

Poker Stars $100+$9 No Limit Hold'em Tournament - t500/t1000 Blinds + t100 - 7 players
The Official 2+2 Hand Converter By DeucesCracked Poker Videos

SB: t28093 M = 12.77
BB: t18198 M = 8.27
UTG: t27787 M = 12.63
Hero (UTG+1): t35744 M = 16.25
MP: t86654 M = 39.39
CO: t49849 M = 22.66
BTN: t67616 M = 30.73

Pre Flop: (t2200) Hero is UTG+1 with 6 7
1 fold, Hero raises to t2150, MP calls t2150, 3 folds, BB calls t1150

Flop: (t7650) 5 7 7 (3 players)
BB checks, Hero bets t3494, MP calls t3494, BB folds

Turn: (t14638) A (2 players)
Hero bets t7500, MP calls t7500

River: (t29638) A (2 players)
Hero checks, MP bets t73410 all in, Hero???

Very villain dependent. I'm not sure how many Aces get to the turn that flat pre from MP1 and presumably float a rainbow, paired flop. For many villains, I think it's often an overpair to the flop that's turned into a bluff. Also, this play could fit into the "sometimes spewy" description... not sure though.

Upon second look, you only have 22600 behind so I can't imagine folding.
I also am not crazy about EP steal-raise but the blinds are short and whateva...

I def snap it off here. First, as Sinking Ship said, it seems tough for him to have an ace here. I guess it's possible he floated with some Ax hand with a bdfd, but he's probably less likely to do so in a 3-way pot. Also, once you check the river it's somewhat more difficult for you to have an ace, and given that he can never ever expect you to have a seven as the utg+1 raiser, he's probably more apt to turn some pair into a bluff here (perhaps because he thinks you'll turn over a better flopped overpair when he checks behind).

Shove river yourself. I'd end up clicking call as played

The Ace is the best card for you to a make a bigger turn bet and try to represent it ; it would make river a very easy decision .
As played call if you do not mind to choke on it ; personally I would .

why would OP want to do that?

hard for villain to have Ax here, i can't imagine folding.

also, i'm a fan of opening the small/medium suited stuff like this when we can but how much do we really like OP's open here, given that we're close to bubble with an exploitable stack size and 3 players behind us all cover?

With his line you will often lose. given your river chk it's a call. bet/eval river

he has 22k left with a 29k pot out there....how r u bet/eval river?

I like your line so far..... c/c river is fine,
how about beting very small as a fake blockbet to let him turn small/medium pairs into a bluff and shove on you and he might call a smal bet with 88/99/TT which he could check back.
He couldve floated you with AJ/AQ/AT w/e but in that case....nh gg in this case, u cant fold anymore with your stack to pot ratio

its just with turn call they can't ever bluffraise river (they bluff the turn rather than float), so b/f seems theoretically optimal