Have a piston question - are these okay?

I was over at my neighbors this morning helping out with his 360. I was looking at his pistons and noticed a few things. They are new Sealed Power 405P, cast replacement pistons. They are a couple of small gouges/nicks around the top on 2 of them and a small spot on the other one by the ring grooves. Can we file down these spots? He got the pistons when he bought the pick up, so he would like to use them. Any advice will be appreciated! David