https://forums.roadbikereview.com/co...gs-147021.html
RBR is suggesting nickel plating, although I'm not sure about the color. I was thinking anodized, but that doesn't look like an anodized surface coming loose.
You could try to remove the entire coating, and either polish or anodize the rings.
Hmm, that bronze color may be tough to find. E-Bay? Unfortunately the E-Bay pictures aren't very clear either.
I did pick up a set of Stronglight black ceramic chainrings a while ago that seem to be working well. In my cases, 53/34, 110bcd.