0.965" eyepieces were the standard in that era up until around 1980 when 1.25" very quickly became common.
The usual brand was Unitron and they still appear occasionally on Astromart; if you posted a "wanted" ad there it's quite likely someone will reply. Unitron sets were usually a mixed bag of orthos (O) in 4,5,6,7, 9mm; Kellner's (K) 12.5 and 25mm as I recall, and some Huygens (H) which were quite sharp and colour-free but had a horribly small field of view. For example
https://astromart.com/classifieds/as...ow/unitron-set
Also, Nikon made some really good 0.965 orthos too, I think 7, 9 and 12.5mm.
As for what's worth keeping.. the mount looks great bt how well it works can only be decided by a night under the stars in the hands of someone knowledgeable. But if the optics are good the OTA could easily go on a modern mount such as HEQ5 or EQ6.
If you do buy the scope and get it going again, please post some pics !