Do any recruiters or career counselors know what jobs are available for active duty?

Yes, they know. Go speak to a recruiter or career counselor.

When you are done with the plethora of MEPS process for the day, when all is ready for you to see the MEPS Career Counselor, that is when you will find out what is available based on what you are qualified for. If, by some chance you are wanting to keep your MOS and there is a slot available at that time, then take it and you're done just have to do the Oath and wait to ship. If your MOS is not available, then what is available for what you qualify for will be provided to you. You then pick the one that interests you most, do the Oath then wait to ship. You have to remember that the list will change pretty much daily, so what is there when you sit down with the Counselor may not be the list from 3 days prior.

You'll know when you walk into MEPS. Class seats are a finite resource, first come first serve