Hero: 2nd tightest player at table. My usual stakes are 2-5 and villain knows this. Villain is very good at PLO and has played less than 20 sessions of Big O, he's still making some mistakes but generally solid. 12K eff.

BTN 50, HJ double straddles 100

Pre: Co nit calls, Hero (btn) calls, villain (sb) raises to 300, both call

Flop (1000) : AsQh8s
Villain 600, CO folds, hero calls
Turn (2200) : 9x
2 checks
River (2200) : Tx
Villain checks

I will have a lot of hands with no showdown value here, if I bluff them all I will be overbluffing a lot. I also won't have a jack blocker without a straight too often. What are good hands to bluff with here? Both in a theoretical and practical application would be interesting.