[Albert Moulton]

What he actually had is less important thant what he could have had as a range of hands.

I suspect that HU in a game with 136 big blind effective stack vs CO that CO's range to raise on the button, call the min-raise, and then check/raise the flop might be as wide as {QQ+,99,77,AQs,KQs,Q9s,JTs,97s,AQo,Q9o}.

You gave no reads, so his range might very well be like this, or even wider if he is just bluffing with TT or even AK sometimes.

Vs {QQ+,99,77,AQs,KQs,Q9s,JTs,97s,AQo,Q9o} you have 49.533% equity.

Yes, you should have raised more preflop. But he probably would have called a raise to $75, and nothing would have changed much.

I think making a cb was good. And I think once he c/r'ed with only $455 remaining in his stack and $305 in the pot, I don't think you can call the c/r then fold later. And I don't think you can fold. And there isn't any room to raise/fold. So, you're just stuck in a bad spot in a high-variance HU game and failed to pair your Ace or 7 on the river.

The only thing you could have done to save yourself was reraise so much preflop that he'd fold. But then if you do that you lose a ton of value when you take this line and he calls you with KQs, AQ, KK (slowplaying), or even JTs (gamboool!).

Edit: Oh, and avoid posting the results. You probably should have stopped when your cb got c/r'ed. I bet you would have got advice to push along with all the advice to raise more preflop.