If you know someone with a blew up 383 or who just rebuilt one, a used piston would be more than adequate for that job. Rod and all if you can will make it an easy swap. A new set of cast iron rings and a quick hone to break the glaze and you're good.
If the bearing is still grey, I'd use it over. If there is a bunch of copper showing, a new bearing won't break the bank.
