I'd be surprised if Epiphone was "always" part of Gibson, I guess it might be, but I remember Epiphones that had no apparent relation to Gibson. I have a "kalamazoo Epiphone" which has the traditional rectangular blue Gibson-style made-in-kalamazoo label inside, and, on detailed inspection, is extremely similar to an analagous Gibson model. I also have an older Epiphone, from long before the blue labels and when they were said to be an independant company; I've never seen a Gibson at all like it in construction details.

Break/break: this stimulated me to get my copy of Gruhn & Carter "Acoustic Guitars & Other Fretted Instruments." Very authoritative; one of the authors is George Gruhn, of Gruhn Guitars in Nashville, a nationally recognized expert. I'm sure his co-author is also well qualified. They say Epiphone wasn't sold to Gibson's parent company, "C.M.I." until 1957. This would be consistant with what I remember and observe in the design & construction details of the instruments.

(It's C.M.I. that owned Gibson, and, eventually these other brands, as well as Gibson, not Gibson owning anything, not even themselves...)

As for home luthiery- I do it as much as I have time and opportunity (for what that's worth; used to be a great deal more!). Many Epiphones from about that time have necks that can be easily demounted from the bodies by means of 4 large screws which reach all the way through the body from a plate on the back to the underside of the neck; this makes demounting easy for placing the neck under some carefully/gently applied straightening pressure for a few weeks (gentle heat aslo helps). As I recall, the screws are phillips heads, & probably #3, not #2, so PLEASE use the correct size phillips head screw driver, so as to preserve these important screws. I's also very easy to block/alter the angle of the neck (after it's straight) with this design. I've seen these old epiphones where that was the major problem, not the actual straightness of the neck. In those cases it was also necessary to examine the large block through which these screws pass to see if it's loose & needs some judicious bracing/re-gluing, etc. (I have good luck with old-time slow setting epoxy; NEVER use any fast setting glues-the road to disaster!)

Meanwhile many instruments had a brass nut on a steel shaft (the brass is much softer & strips before the steel); if yours' has this feature you just might, if you're lucky, be able to coax the old nut off & find the steel threads on the shaft underneath in acceptable condition, so you only have to find another nut.

Sometimes an acceptable expedient is to get off the old nut and place washers to change the position of where the nut sits on the shaft. The more distal threads are often still intact, so you shim the nut such that it engages the portion of the rod with the threads still intact. Can make the cover plate bulge a little, but it can still work OK.

On the other hand, if it's all steel & really badly stripped you'll need an expert luthier to correctly install a whole new adjusting rod system.

Even though it's an old "plywood" guitar, if it still works well for you I'd consider spending the money.. but.. on the other hand... If you shop carefully enough and have access to bigger cities & true discount prices (which you will NOT find in the otherwise pleasant smallish college town in which I now reside..) the better Seagulls (may have to play a lot of them) with the cedar tops might be hardly any more than some repair shops would charge to repair yours. It's a random process, but the best of them are really very good, indeed. And an entry-level or mid-range, less decorated Martin or, better yet, Taylor might be had at a surprisingly acceptable discount price. I've seen several well under a grand - and purchased a new DM, w/great sound, for an offer too low to refuse. Seen occasional new Taylor's at similar bargain discounts. (My next guitar!) If you can't start at least 40% off the true msrp, [not an inflated BS/rip-off "list" price]with hard-shell case, don't waste your time talking further; go to a different store - or city.

In any case, good luck..

Cheers, BK