Based on the fact that I'd never seen one until that pic you posted, I would have to agree that it is one of the rarest amps from a mainstream company. The fact that it seems pretty much no one really seems to know anything about them and the timeframe in which they would have been made, I would guess VERY low production run. Possibly in the sub 100 range. After the DEI buyout, a lot of the great amps were ruined for the G5 run. I'd buy one if I found it at this point, just to have. Kind of like my Son of Frank, though I have been using it for the last year on mids and highs.