This just ain't gonna happen. Chinese schools will reimburse some airfare, if you're lucky, but no way they'll ever advance it.
If you saw the number of hired foreign teachers who pull a no-show, you'd understand a big part of why...

Bear in mind that when coming to China, you're going to need more than just airfare. Even with school housing, you're going to need some money for personal household items. You're also going to need money for food, transportation, and so forth to get you by until your first payday...which can be as much as a month after you start working. Then there's always the odd chance that things don't work out and you need to either move or return home...and live until that's completed.

Don't come to China in a hurry or on a shoestring. Do it righteous or don't do it at all.