Tucker,
I am a current Navy nuke (ELT/MM1) who is "going" (distance learning) to Oregon State University for my MS in Radiation Health Physics. I went up there this summer and met many people from many different types of jobs, including a medical RSO and a medical physicist. It sounds like you are/were a RHO. A medical physicist would be more along the lines of x-ray machine calibration, radiation therapy dose calculations, etc. The RSO would be more concerned with the worker protection practices used during these medical procedures (I hear the most notorious problem is getting doctors to wear their dosimetry). Sometimes, these people are one and the same. The only problem with medical physicists is that most everywhere requires 3-6 years of experience prior to getting their job. If you are in a hospital setting as an RHO, you should be fine for this. From the information I gathered, the medical physicist in a cancer therapy setting tends to work alot (80+hr weeks), but they get paid a lot (100K+). As far as a university, I'm not sure how and if they promote from within, but on the Health Physics Society website a few months back the University of Minnesota was looking for one, and right now USUHS is looking for one.
Jason