I screwed up the title. unknown villain had the river overbet and I had the straight.

so I was just stealing on CO and hit my gutshot on the river. the guy then decides to overbet. what is the best move considering villain is unknown? shove/raise for value, call or (lol) fold?
I'm only interested in the ending. I know I made a small cbet considering the size of the pot etc etc.
what is he representing there?

just some more info: it was pretty deep in the tournament (like, top 20) and I had a ~136bb stack vs. a ~75bb stack

Poker Stars $1.00+$0.10 No Limit Hold'em Tournament - t400/t800 Blinds + t75 - 6 players
DeucesCracked Poker Videos Hand History Converter

Hero (CO): t109489 M = 66.36
BTN: t9398 M = 5.70
SB: t60850 M = 36.88
BB: t11357 M = 6.88
UTG: t28502 M = 17.27
MP: t50537 M = 30.63

Pre Flop: (t1650) Hero is CO with 8 T
2 folds, Hero raises to t1600, 1 fold, SB calls t1200, 1 fold

Flop: (t4450) 6 9 A (2 players)
SB checks, Hero bets t1600, SB calls t1600

Turn: (t7650) 6 (2 players)
SB checks, Hero checks

River: (t7650) 7 (2 players)
SB bets t17600, Hero ?

fold pré

as played: call

You can almost never raise this river because you will normally only get called by a boat without further reads.
You don't provide any reads on villain nor how you have been playing.
Flop cbet is a tiny bit small but that's okay cos you get a bunch of folds from kq kj 88 more often that not.

In b4 wanted to raise river, smooth called and he had 65hh and you're tilted you 'missed' value.

Usually this kind of bet is either something which is pretty much the nuts or air.
I dont think he would bet an ace this big and the only hand in his value range you beat is 6x which is pretty unlikely.

So call.

Plus 1

that's not it.

also, does everyone really fold 8To in CO position during a deep 6-max tournament? I mean, I know it's not an insta raise, but I don't see how stealing with that hand in this situation is that bad. can anyone explain?

lol :'/

$1 mtt vs unknown this is not true, as played snapcall! toooo bad if he had a boat this time.

At least call

Pre is a little marginal with BTN & BB's stacks
Call river >>> anything else in a 1r