I was never in the military but I work with many that were... I **think** just the AF and Navy are your best bets for becoming a military controller. I work with a guy that was a Marine and was a controller (in Japan) but it is my understanding it's a tough gig to score in the Marines. Not all Navy controllers go to sea, a buddy of mine did 5 years in the Navy as a controller and never saw a ship. Most do... former Natca president John Carr was a controller in the Navy and was on carriers most if not his whole time.
Check out -
http://www.stuckmic.com/
It's an ATC message board with the majority of guys being military controllers, you should be able to get some good info over there.