reworking stock heads or buy aftermarket?

Putting standard pistons in ten-over holes is very possible. however the piston slap would be incredibly noisy, and it wouldnt go away. It would be unmistakeable.
Lets talk about the pistons for a sec. Are they location specific? That is do they have big n little valve pockets or eyebrows on the top?If they do not then there was an old trick we used to do. We would take the oem pistons off the rods and spin them around 180*. In those days pistons had offset wristpins to help quieten piston slap on cold mornings. By reversing the pistons the thrust went ever so slightely to the other side, which we were told would free up some hp.Perhaps this was done in your engine.It would make sense.
My brother had some wild buddies back in the 80s. They would go out bushpartying. He tells a story about this one time. They got bored I guess, and decided to see how much abuse a 318 could take. They bricked the gas pedal wot and went back to partying.When they finally got tired of the screaming teener, one brave lad went over and shut it off.It never restarted.Well thinking it was a sure goner they gave it to me. Of course I was 10 years older and had tools. After a bleak compression test, I pulled the heads. And dont you know it, every single intake was bent, and had scarred the piston.As I recall it the exhausts were ok.I replaced the heads with some recondition ones I had,changed the oil and she was ready to go another round.Thats tough.So thats my thinking on the piston scars. Buff em smooth if you feel the urge.