ok to reuse these parts during rebuild??

Hi guys, my friends 97 mxz 670 needs new pistons, we ordered them up from denniskirk.com so we can get the asap but they did not have roller bearings in stock. we just got dumped on with 12"+ of snow and want to go riding asap!

so my first question is how acceptable is it to reuse the roller bearings at the piston pin?

second question is the cylinder head ended up with some pitting on the one side from melting piston chunks flying around. can we just sand paper it smooth and use it?

thanks

ok to reuse these parts during rebuild??