There's a 3M Versaflo PAPR on Amazon right now for $560, which is weirdly cheap, with most being in the $1200-1500 range. It's a whole system, with a comfortable mask, back-of-the-head hose placement, an included flow testing gauge, and 3M's reputation behind it.
There's a bunch of cheesy no-names that take old-school screw-on NATO gasmask canister filters, for $100-200. They have dubious batteries, reused masks from other purposes, front-of-chin hose placement, no testing, and they're sold under a suite of new keyboard-smash brands every week.
I really wish there was something in the middle. I'd love one that runs from Milwaukee batteries, since from 3M's accessory pricing sheet, the battery system seems to be a large part of their development cost. I can't imagine a reason that a PAPR should require different filter media than a 6000-series half-mask, it'll just need more filter changes because it's moving more air. The flow tester and masks should all be interchangeable.
An affordable-but-reputable PAPR would probably find a lot of buyers these days, but nobody's serving that market.
