It was never a one-off, they built a whole bunch of them - they were the earliest Rippers, but the shape was discarded due to weight considerations - the later shape featured a huge pg that allowed for excessive routing to combat weight.
The guy who sold me mine had connections to Gibson and told me that inter alia Greg Lake made a visit to the plant when they had a dozen or so of these around in '72/'73 - different woods (there were maho ones too) and pup configurations. Jack Bruce was involved in the early designs too, but jumped ship when he didn't like where it was going.
There is not much of a dif in tonality to an early regular Ripper. Lurking underneath these mudbucker casings are the same sidewinders that were later under plastic.
The Rippers were for Gibson standards at least a moderate success, but I doubt that this would have been achieved with the early single cut shape. Both weight- and size-wise, those were ungainly for anybody but the very tallest players (with well-developed shoulder muscles!).
PS: The bridge on mine is not the original three point which made a sensible action impossible, so I put a Blackbird three-point on it (my Blackbird has a Supertone bridge) which went quite a bit lower. The plastic saddles, however, were featured on the original as well.