That's a mighty good friend, indeed ! Congrats !
What model of Marlin .25-20 rifle do you have ? (the model should be on the top tang)
I'm far from expert, but AFAIK, The only Marlins with two FP's were .32's - and I don't believe there was ever such a cartridge as the ".25-20 Rimfire".
IIRC, the only .25 RF cartridges were the .25 Stevens Long & Short, the .25 Bliss, and the .25 Bacon - all long obsolete, and expensive collector's items today.
I have no clue, as to whether or not a .25 Stevens would chamber/fire in a .25-20 chamber (with a RF firing pin, of course).
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