I just bought a Marlin 336A, 30-30Win, 24" barrel, 1/2 length tubular magazine, New Haven CT, #E34213, Walnut stocks, according to Marlin made in 1948. Marlin indicated that it might have some collector's value. Can anybody confirm this?

Deke.

I might recommend Beltloop over in the classifieds. He seems to have lots of Marlins available and knows quite a bit about them.
Good luck
Frank

collector value? probably not much because they are rather common but the shooter value is very high! Use but don't abuse and enjoy it.