I just saw a very nice used Series I long scale 4 string at the Philadelphia Guitar Show. It's an '83 in near mint condition, very nice quilted maple top (unusual for that era) with a mahogany core. Fairly light weight given the woods. Comes with the power supply. The dealer is asking $4,000 U.S.
The dealer is Rock 'N Roll Vintage in Chicago, IL.
See the bass here:
Quilted Series I Will somebody please buy it before I do?