JM stamped 336 Marlins are pretty desirable right now from what I have seen, especially pre 1983 without the crossbolt safety.
Also from what I've seen 336's in .35 Remington go for a good bit more than 30-30's, about $200 more.
I have 2 336's in .35 Remington, 1960 vintage and 1980 vintage, both in very good condition, and if I had to sell them, there is no way I'd take less than $800 for either of them.
Additionally, I had a 3rd 336, also in .35 Remington, 1972 vintage also in very good condition which I gave to Qtips nephew. When his nephew told a co worker what he had the co worker offered him $750 for the gun sight unseen.
