The MIN must have had a fairly short production run.
I’m not sure when the MIN was released, but it seems to have existed back in 1986, as it appears in the first brochure in this thread (which should also be somewhere in the NFPA archives). I couldn’t find any ad for the MIN earlier than the linked one from 1988, so it could have existed for longer.
Also, if this provides any more information, the MIN-12 and MIN-24 are still UL listed.