Unfortunately there's too small of a demand for longscale Gibson SG-shaped basses. The SG-Z was no blockbuster.
Speaking of, this looks pretty nice, though i don't know what "TV Pelham blue" is. I guess because you can kind of see the wood grain? https://www.ebay.com/itm/123121217400?ssPageName=STRK:MEWAX:IT
The SG-Z's pickups had almost no fundamental. They looked like TB+ but weren't. Really beautiful bass and balanced well (at least the one I tried). Shame about the crappy tone, though.