Depends... on quantity your guess is probably accurate however I would wager that the 6P & it's derivatives have been copied over & over & over & a whole bunch of original clone brands out there were some sort of "fire" branding as well.
At one point it was so bad one company would sue another one, win and the loser had to keep making copies with the winners brand name on it as the penalty.
I wonder what the sales numbers were back then compared to today. I would wager that more lights are sold in a year today due to population size/economics than were sold in 1-5 decades again for the same reasons.