Not enough information given to answer this question.
Your serial number indicates that your Marlin model 30A was made in the year 1979.
With the serial number that you provided,your Marlin model 1893 rifle was made in the year 1899.
This would be best left to a qualified gunsmith to do.
The letter F prefix to your serial number indicates that your Marlin rifle was made in the year 1949.
A marlin lever action 30-30 rifle can hold fife shells in the magazine and one in the chamber.
there is a marlin collectors site or gunbroker.com
50-350 USD or so
I would check the lower tang,under the lever.
The Marlin 3030 model is a classic hunting rifle made in 1902. The value of this gun today can reach several thousand dollars.
The R prefix to your serial number indicates that your Marlin model 336 rifle was produced between 1957-1958.
Never fired, probably 500.00 in pristine condition.