Are they Benzonis? They look like they might be the magnesium wheels, not the later aluminum. I recently refinished my son's '86 wineglass wheels, made by Speedline, buy I think they're of a different, more true aluminum metallic finish.
Maybe somebody else here can provide you better confirmation than I can.
I used a duplicolor silver wheel paint with matte clear coat - very close the original finish that were on mine in color but with a hint of flake, the originals were flat gray (close enough for me anyway).