Don't know of any down by your area. Have you tried asking any of the dealers down your way? Bower's board has a listing of Class III dealers (C&S Metal Werkes in St. Charles is on the list but there are a several hour drive from you). There is a shop in Houston that you might try. Can't remember the name. They might be able to point you in the right direction.
BTW, my grandparents had a place outside of Harshorn many many years ago.
Almost forgot. The range I help out at in St. Louis just got their Class III license. The Bullseye, at 5100 Manchester. They also have some FAs for rent (Steyp M69, Bushmaster, MP5 and 1919A4 Browning in 7.62 NATO right now).