I've had a Japanese knock-off of a Fender Jazz Bass that I've been playing for two years now. I'm curious to see when it was built and by whom.

The only identification on it is the word 'Japan' on the metal plate where the neck bolts to the body. The headstock is completely free of any text or identification. Judging by empty screw holes, there were originally bridge, and Neck Pickup covers, and a thumb rest on the knob side of the bass. The bass has a good amount of scratches/dents and the wood and inlays are quite aged. It has a rosewood fretboard, block inlays (even on the first fret), and the body is sunburst with a three layer red pickguard (black, white, red)

If you could please point me in a direction where maybe I can find some info. Thanks!