Just got a 336 transferred to me that I bought online.
It has S/N 2000XXXX making it a 1980 model. It has no cross bolt safety. ]
The barrel has markings "THE MARLIN FIREARMS CO. NORTH HAVEN CONN., USA EST. 1870-MICRO-GROOVE BARREL-MOD.336 CAL.30-30 WIN".
I am needing to buy a couple...