No, they made thousands of Marlins in 1970 with the stock medallion; only dealers trying to fool someone over how "rare" these models are ask a premium, and some guys don't like the looks of the medallian and avoid that model altogether. As to the "rust rash" on your gun, it is probably the result of imporper case storage. Disassemble your gun, being careful not to booger screw slots; once you have the gun apart, take some fine 0000 steel wool and quality gun oil; apply the gun oil to the metal surfaces and carefully work the damaged surfaces with your steel wool. This treatment will remove the rust skim and not damage bluing; but will not remove metal pitting. Clean all the other parts while the gun is disassembled to include the inside of the magazine tube. When finished, rub some Old English scratch cover into the stock finishes and you will be surprised at the resulting warm wood glow. Good luck