Also available for Android on Google Play.
https://play.google.com/store/apps/details?id=musc.exposurenotification&hl=en_US&gl=US
The brand our hospital uses is Halyard. They come in blue, yellow, green, and purple as far as I've seen. I did a quick Amazon search and there are a couple of sellers of Halyard on there but I can't speak to the quality/actual product unless it's for sure Halyard. My guess is Halyard is mostly selling directly to hospitals and clinics.
Based upon reviews and customer photos, if I needed to purchase some masks I would probably get these. I am not familiar with the brand or seller at all, but they look solid/appropriately shaped. I have reused the same surgical mask for weeks when out in public and store it in a paper bag when not in use. If exposed to a known positive case, I throw the mask away.