Ron
Your 3 points addressed in order:
She thinks.
Chances are she doesn't know. But you can only take these things so far.....
The similar scenario with mine is that for reasons unknown the former owner removed and discarded all the height stops from the quick change tool holders, thus rendering them into slow change tool holders - and he did that why??????
Also, he removed and discarded the "bridge" that retains (goes under the bed) for the 3 point steady and discarded that - why?????
We are talking 1980s lathes. 40 odd years is way longer than most technology goes without 3 or 4 or more generational changes in design.
There is an online sourcing site (bit like Alibaba) for Taiwan, see if you can find out its name and have a look in there for one of the original companies. IIRC a number of those names are mentioned in this thread or other threads about Taiwanese lathes, say some of the ones that the Yanks have that have been nameplated as Jet, Enco etc. At the end of the day, they all came from about 12 companies in Taiwan.
Mine is a Shenwai. I am told that it is very early as it does not have the step where the Norton head contacts the bed. But having said that, the latter stepped ones had the same tail stock to the best of my knowledge.
Hafco never sold mine either, despite their sticker being on it......
Ultimately, you need a tail stock with the same footprint ie., same bed cross section and with the same centre height. Other than those 2 criteria it can be any shape or design, it just has to fit.
Regards
Doug