The bass you're looking for is a Yamaha SB-5A
. One recently sold on ebay for $500 shipped.
Like mr.mow above, most first hand accounts of the original examples from the late 60's have them as terrible instruments. Very cool looking, but they're poorly built and sound bad.
I can tell you first hand, this is NOT the case with the made-in-Taiwan reissue, the Yamaha SBV-500.
I bought one on a lark a few years ago, and was stunned to find that this bass was beautifully built and sounded great.