The OP got a great deal on his Nashbar bike. Japanese quality – what’s not to like?
I suspect eighties Nashbar bikes may be scarce because many bikes sold by Nashbar in that time period likely don’t have Nashbar decals on them. Decals weren’t necessarily applied at the point of production.
I purchased an Italian roadbike from Nashbar circa 1983. The frame had the Columbus SL decals, but the Nashbar decals shown in the ads were loose in the bottom of the shipping box.
Nashbar may provide good deals, but it doesn’t have much panache as a name in cycling, I expect many buyers did what I did and left the decals in the bottom of the shipping box. I still have the frame (and very nice it is too). It has never had decals on it.
A couple of years after I purchased it, I ran into a fellow who had an identical bicycle. His frame was festooned with Olmo decals. When I asked him about the decals, he claimed that he had telephoned Nashbar and had been told that his frame was made by Olmo. So, somewhere, he acquired the Olmo decals and stuck them on his frame. In truth, if the frame had had the Olmo engraving on the fork crown it would have been virtually identical to high end Olmos of the time period.
I think this is called brand name engineering.