When trying to sort out who made what from anything coming out of Japan in the 60’s and 70’s it’s really easy to get lost quickly. Unlike a lot of American companies, a handful of Japanese factories, built dozens of bass guitar brands.
“Japanese Manufacturers of Made In Japan Badged Electric Guitars from 1960 to 1980” by Torch Harrison is a fabulous resource that sorts out a lot of the confusion. The article list many Japanese factories, with brief histories, and talks about the brands that each company made.
Please check out this article on Hub Pages.
As well, Bass-Aholic list over 30 brands of Japanese bass guitars. I’m sure there are many more, so check back because this list is always being updated.