Hi micfranc.
I've been looking around since you first posted this thread and I think your guitar was likely built by Kawai. I haven't been able to find an exact match to your model but the trem unit, knobs, pups, etc. were used extensively on Kawai guitars.
This 1968 Kawai is the closest match I've found so far. Obviously, not your guitar, but there were not a lot of builders producing solid teardrops during this period. I frequently run across undocumented Kawai guitars; I think you may have one of them.
