The thin wall pins are clearly dimensionally compatible with my R100 Pistons. So they may not be oil head pins. I guessed based on the photos of the individual part on the fiche. Although the fiche lists size for airhead pins, it does not for the oil head.
I asked the shop to send me one more of each, and I'll decide on Sunday.
As for the plating, the chrome is definitely gone in the middle where it was exposed. I even took the buffing wheel to it to see if it would get shiny again. But it actually is textured and is unusable.