What do I do if my mos is unavailable in renegotiating? And what can I do to get out of DEP if I can?

It's very unusual that USAREC is going to let you renegotiate 68W is the second largest MOS in the Army so there are probably lots of slots. However you cannot stay in a DEP status longer than a year. If the job you want doesn't have a class seat that ships out in less than a year from when you joined the DEP, then you can't take that job. If you don't ship by the one year mark you are a DEP loss

If you are a DEP loss good luck finding a Recruiter willing to risk hours of wasted time getting a waiver for you the second time around.

There is a lot of misinformation here. First of all, if you opt out of your current contract and do not ship to basic training you don't need a waiver to enlist again, although it will make it tougher on you finding a recruiter that is willing to take a chance on working with you. Secondly, the way you end up in the Army has no bearing on where you will get stationed or what your MOS will be down the road. The MOS in your contract is the MOS you get unless you make yourself unqualified by getting a criminal charge, not finishing high school, failing AIT, etc. Bottom line, you need to speak with your recruiter. They can submit a USAREC Form 601-210.22 (Request to Change Enlistment Option) which has to be approved by the Recruiting Battalion Commander. If/when it is approved you can go back to MEPS to try and get a different MOS. At that point you have three choices: choose an available MOS that you qualify for and ships within a year of your original dep in date, keep your original MOS if none of the options presented are to your liking and ship out as planned, or become a DEP loss. To reiterate, though, this entire scenario has to be discussed with your recruiter and approved by the BN CO.

Keep messing around with your contract and you're gonna end up a cook or a grunt down at Fort Polk or Hood.... Just saying...