The owner has released a video. It seems that it's on a Maneater PCB stack with some heavy modification via wire jumpers. Possibly an altered sound PCB as well. The PC Board # on the serial number sticker on the cabinet is noted as "6-21-78" followed by initials, probably of the QA person. That's probably good enough for use as the release date in https://github.com/mamedev/mame/blob/master/src/mame/drivers/pse.cpp until more info becomes available.