well standard bore is factory so honestly you cant really use that unless you sleeve.... you can go with oversize pistons if you like....

id get first oversize and have the machinist bore it to the proper piston wall clearance with the final hone.... that way its perfect.....

im sure theres a bunch of ia members that could point you to a good machine shop to do the job....

you should need a hot tank bore and deck. youll be straight