Not necessarily a suggestion, but here's what I did to beat that weird alloy once. I bead blasted the receiver and then had it electroless nickled, ended up a soft gray color. I then blued every other visible part of the gun. When re-assembled it had a striking appearance- the blued parts against the electroless nickle made for a pleasing contrast. It endured some nasty weather, and still looked great years later when I sold it.
