383B Stroker Build

I just picked up a 1968 383 complete engine for 150$

I want to go stroker, N/A, raised port aluminum heads and run on pump gas with it.

First I need to figure out what stroker combo to run.

I see 440 source has 2

383>>496, 4.250
383>>438 3.750"

Why isn't there on with the 4.15 stroke??

Is it possible to put a 440 crank in this engine? I'd assume yes, just needs to be cut down right?

I'm all ears to options and recomendations.