T,
Back in the 1980s/1990s when those scope were made, most Simmons scopes were made in Japan. Most likely by Hakko or Light Optical works- the same places that built the Japanese Tascos and Bushnells of the era.
I have owned a few of them over the years. While folks make a big deal about them being "old" quality Japanese optics, I never saw them as being top tier stuff-. Good, but not on the level of a B&L Elite, Leupold etc..The lenses were plenty bright, but optical carity and shaprness was lacking on the ones I had.
The $400 price figure is pretty suspect. I cannot recall ever seeing a Simmons scope- no matter what the vinatge or model -ever priced over $200 brand new in those days.I cannot see a used one being worth more than $150.