So you will have undergrad debt, MA debt, and then go to a PhD program?
Let's say you get funding to do a PhD program, the ideal situation. That's great, but it means you're lowly paid while you have six figures of debt over your head. That's not a good place to be in. You'll be paying that debt back forever, which is not a good feeling.
Let's say you don't get funding to a PhD program but still go. That's not so great, and now you'll have undergrad, MA, and PhD debt when you graduate. I don't know how much undergrad debt you have, but you're looking at at least 7 years of debt for your graduate degrees. This is real money for someone working on Wall Street or in corporate law, much less someone on a tenure track wage. I just don't know see how the debt is sustainable in that situation.
It really seems like getting a job after the MA is the best course of action.
Student loans are not dischargeable in bankruptcy court.