infinitives - I'd better get a quart

I'd better get a quart. (daum.net)

There’s a had better usage in the above. I’m not trying to figure out what the original it would have been, but can this construction below be made? (When I, the main verb, is logically the object of the non-finite verb - get, it could be thought as a tough movement. But it's not the case.)

I’d be better to get a quart.

Answer

Did you mean to change it to a question, or to ask if the following is sensible?

I'd be better to get a quart.

If you said that to me I could respond by making a quizzical face and say:

"I'd be better to get a quart?"

(...as a challenge to the fact that I didn't understand what you just said, because it sounds weird.)

Yet it could pass for old-timey pirate language, as a sort of short-hand for "I'd be better off if I were to get a quart."

first mate: "Cap'N, would you like me fetch ye a gallon of skunk whiskey?"

cap'n: "Arrr, nay! I'd be better to get a quart of yonder Basil Hayden."

If you spoke like that people would know what you mean (and that you were a pirate). But it's not normal speech, and you should go with "I'd better get a quart."...assuming you live in a place where people know what quarts are.