wasn't there a chrome shortage during and after the Korean Conflict? cheap [low chrome] SS was used back then as an alternative to chromed pot metal
SS pitting isn't unusual with
low grades of it, especially with bleaching chems, pulp mills deal with it regular ... happens in marine applications too ... someone may also have tried to clean the emblem at some point with steel wool which transfers the iron to the SS surface [like welding splatter]
Bill