That's right four hundred forty masks (6 cents per). Yes it's Amazon but this is a good deal.

This is the link: https://www.amazon.com/dp/B08J1THV9G

It is from a sub-company of Amazon that specializes in deals so it is legit-ish. The ones a close friend received came in an official 3M branded box (a huge brown box not retail packaging).

They're individually packaged in the official sealed wrappers, had lot codes on them and looked to be in good shape. No weird smells either and the elastic and nose pieces seemed fine. No expiration dates unfortunately if that's super important but the box had a barcode and I suppose you could contact 3M and ask about that lot number.