ashdd81. Ouch. My brother-in-law got caught in that situation: too expensive for a new study, and for a new machine.
I use a Philips Respironics DreamStation - which is pretty new on the market.
It uses something that isn't a mask, as I understood it, and got with my first CPAP, in 2003. "DreamWear under the nose nasal mask". Also called a Nasal Cushion. The cushions come in S, M, & L.
There was 1 or 2 "masks" that had a nasal "insert", prior to that.
Not sure which numbers on the package count, but REF 1116700, and or the Medium: 1116741.
The "headgear" is minimal and works for me and several others I know.
No idea what they cost, these days. Medicare covers some of it, but I'm over 70.
Not sure what other brands exist, and what other models are still supported. Might be worth asking Phillips; there are sometimes discount coupons, sometimes based on need. A Doctor might help?
Good Luck.