Did I get max value from my nut straight?

[chopchoi]

1/2 NL. I have $200. BB has me covered.

There's 1 limper already in. I'm in LP with AJ. I limp. BB raises to $6. Limper folds, I call.

Flop: KQx, rainbow. Limper bets $7. I call. I know I don't have the odds, but I figure implied odds are good, because if I make my straight, and he makes another 1/2 pot bet on the turn, and a decent bet on the river, he'll call a big raise.

Turn: T. He bets $7. Do I raise here or wait till the river? He's betting weak. I don't think he has much. Probably AQ. I decide to wait till the river. If I make it look like I'm trying to buy it, maybe he'll call.

River: x. He bets $7 again. I raise $21 more. He calls.