By coincidence I have a Glenfield 25 and a Marlin 25N, so I took them out to compare. The Glenfield 25 is from 1978 and uses the old style of magazine with the release lever built into it. The magazine clips onto a metal piece up inside the mag well. The Marlin 25N is from 1995 and uses the newer style magazine. That gun has the mag release built into the base of the mag well as part of the rifle. The bolts seem a little different as well. I checked Numrich's and the parts numbers are different for the bolts so I think they are not interchangeable.
I would guess that many parts are similar, and some may be interchangeable, but not all. I know the older style mags are available because I just bought a couple, but they are getting pricey. I paid almost $45 for two shipped from Dick Williams.
Check Numrich's or Brownells for specific parts.