Former AF here, got out in 07. Been through USAF SERE School and had a good buddy that was an instructor.
To my knowledge, your son should be able to do either a 4 or 6 year enlistment with that career field. After basic, he'll go to indoc at Lackland and if he passes that he'll be off to Fairchild for a 6 month tech school.
Go here for more info: http://www.gosere.af.mil/
It used to be that most bases did not have dedicated SERE instructors, they were all at Fairchild. So, after I graduated the course, I was assigned to be the survival continuation training instructor for my squadron. Eventually we got a SERE instructor on base so he took over that duty, but we hit it off so I got to tag along and be his defacto assistant. I had a blast doing that stuff and my buddy loved being a SERE guy.
I believe these days, every base with a flying squadron will have their own SERE personnel to perform the continuation training. So after your son does his time at the school in Fairchild, he may be able to PCS somewhere else.