If the frame was made before 2008, it's matte nickel, as marine said, the only SS H&R frame they've ever made comes on the 45-70 and 444 Ultra Hunters. Stainless used in firearms has magnetic qualities. FWIW, my SS Ultra Hunter has a blued barrel release, my matte nickel frames have nickel barrel releases, dunno if that's definitive for all tho.
Tim