Not sure which of us you're directing the question to, but I'll jump in and hope I'm not cutting in line ...
NO NO NO NO NO NOOOOOOOOO .... please dont confuse infrared saunas with red/NIR light, altho they're similar. The diff is that the sauna version has more to do with generating heat production, and there's no control over what frequency or wave length of light you're getting, a recipe for disasters of various proportions.
Check out the links to the 2 PR threads I posted for you, and do a little google. Some of the set-ups are $$$$, others are more modestly priced .... you need to decide what your needs are and what you want to spend on this ....there are endless options on the internet.
You also need to learn a little about what distance to maintain from the light source, how long each exposure should be ..... you'll read a fair amount about closing your eyes during treatment, but in Europe, red/NIR light is used to heal the eyes of various ills. It's a question of how long, what strength, what wave length ...
I'll dig thru my notes and see what I can find. I was considering this before recent developments overloaded my ability to take on anything more adventurous than cobbling together something for dinner ....