[PantsOnFire]

Let's look at the stacks and the pot. The pot is 325. You have 1125 and he has 980.

So what is beating you? AA, Kx, 33, 55, 53. That's not a lot of hands and AA and 53 seem unlikely. Plus, there is one K on board so that reduces Kx by 25%.

In this situation, I think you have decide right away if you are going the whole way with this hand. If you are not, then I would bet about 250 on the flop and then fold to a raise or check/fold the turn if called. That's pretty weak IMHO.

If you decide you are going all the way, then I push on the flop. You may even get him to lay down something like K2. You are not "way ahead" here unless BB has a complete trash hand. If he has any piece of that flop he could take the lead with the turn card. So checking and then moving in on the turn might win you a bluff bet but you risk losing the entire pot not to mention most of your stack, even with only a few outs for villain.

Personally, I push the flop and hope for the best. He may even see this as a bluff and call with something like A5 or A3 or a lower PP.