I found this midwife who does home water births:
Also I am not sure how far away S.C is but there is a birth center there that does water births I believe...
I found this about tricare's coverage:
Here's some ladies talking about their experiences with tricare (one lady at least had a waterbirth):
I had a waterbirth with my first and it was GREAT!. I am in WA State though, I think it's a bit easier here. Best of luck to you.