The only thing I could find is...
Arizona
David's Camping Oasis in Bisbee AZ
Texas
Circle J Ranch and Cattle Company Eustace TX
Missouri
Cactus Canyon Campground Ava MO
Kansas
Camp Gaea ...somewhere between Kansas City and Topeka
I got this information from Naked Places by Michael Boyd, you can order it on line, it lists all Naked Places around the world!
I'm going to move this to ETC...maybe someone in these states will be aware of something else not listed. Have a fun trip