I'm a new user of a scleral lens, so there are others that can share more than I can. I'll give you what I can. A scleral lens is one that is larger and deeper than most lenses. There are a few kinds, so use the internet to look for details. Mine was available thru my optometrist, but there are doctors that can be found on the internet for your area, I'm sure. Though originally developed for those with misshapen or scarred corneas, they are being used by those of us that have dry eyes also. The idea is that they keep your eye bathed in a saline solution, so dryness won't bother you and you won't do damage to your cornea.
My doctor suggested I start with the GP kind because he thought it would best protect my eye. I'm up to about a 7-hour stretch with them. I also wore contacts years ago and I think that helps with the adjustment period. My eye doctor submitted it to my eye insurance as "medically necessary" and I think it will be covered. Not all are successful with that, but so far it's looking good for me.
You should look in the "eye issues" section of this site for threads about scleral lenses. It was very helpful to me. My doctors had never used these lenses with patients like me, but were willing to try when I shared what I'd read here. So far, my scleral lens is working really well and I'm more than pleased. I hope you'll have good success too! Let us know if there's anything else we can offer.