20$ | 6 max | T | post | K7s

Depends of player on how much you expect him to make calls on flop. Kx with flush blocker is almost mandatory call. Without it bit less of call. This K7 is one of worst Kx imo in that your kicker is small, it doesn't block flush and it blocks bit of hands like 76 that could well call flop. It's possible villain calls with hand like KT on flop especially if having one diamond and value bets river. Though I would expect sizing to often be smaller so this is more often flush or trips imo.

So most of time versus this size I would prefer folding. I think around half pot we have to call.

Seems like a easy fold on the river or you have decent reads he can bluff here.
You beat nothing of his value range.

Cheers,
SDK1987