The finish on a couple of mine is well worn, I just live with it.
Lots of closet guns show some oxidation after a few decades. PM is the best answer, regular coats of CLP, SLIP 2000,oil, etc, cost little in time and trouble.
Sometimes very light rust can be removed with LIGHT rubbing with 4/0 Steel wool soaked in oil.
With care, that 1969 WM will feed and protect your grandchildren....