Unofficial editions have been around for several years, but now EPE has announced that "Gladiators" on DVD is "coming soon". Mentioned in the PR material is one of Elvis' main Elvis' training partners, Wayne Carman.
Wayne wrote a book, "Elvis's Karate Legacy" (released in 1998 by Legacy Entertainment Inc) about his martial arts relationship and friendship with Elvis. Elvis In Print: The Definitive Reference and Price Guide says of Carman's book:
"Excellent examination of Elvis’ love for karate written by one of his training partners. Features some great color photos of Elvis sparring and in class."