As far as I have seen
quite a few turn up and always in basements thank god, they are too heavy to move so people let them just sit there until nuts like us come along. So I would guess based on that, Avco Manufacturing sold a ton of these Combos from 1953 to the end 1958,then everything was switched to the tiny Philco machines and factories. Not the same machine.
This machine had the highest spin for a front load combo in its day, it was the penn-ultimate. At 525 rpms, and that big drum, it does take out a lot of water, but drying in 35 minutes is even by todays' standard, speed drying!
First developed here, These were fast powerful machines and they deserve a big place in american history they were so revolutionary for their day.