There is cheaper tech out there....I'm still researching all the alternatives. But a positive pressure unit is ONLY needed by people who might suffer from hypoxia when using a standard mask. A regular mask works.
I know what the positive pressure masks are for or can help with. My point was that they are quite expensive comparatively. At any rate, getting PPE on the consumer side right now - even specialized PPE is pretty tough considering they are reserving a lot of if for medical and the rest has been bought up or hoarded long ago. To get a respirator (reusable) and filter cartridges, you’ll have to order and wait.