If you are guard or reserve, I would suggest just bumming it till you hit 750 and then apply to the regional of your choice.

this ^^^^^

I don't know your exact situation or how many hours you have, but here are some issues I've seen...

Flight schools are hiring like crazy right now, especially if you are willing to move.
Some flight schools are requiring new instructors to sign a 1 year contract.
Some schools don't, but guys who are close to reaching the R-ATP minimums are having trouble getting hired because the schools know that they will leave as soon as they came. I worked at a flying school and they didn't want to hire a 1200 hour instructor because they said it cost them so many man hours to get the guy in their system, they would rather just hire a low time guy who is going to make the cost of worth it. So then, these guys can't get hired at a 121 operator because they are short of the requirement. They end up going to part 135 operators with a 1 year contract.

I believe all three American Airlines wholly owned regional have cadet programs, I know PSA does for sure, since I work there. More info on that is here.

While the current state of the WO'd regionals is well documented and debated here, I personally believe that going forward there will be some long term benefit at being at a wholly owned carrier. In the words of AA's CEO, placing flying at a WO means they're not paying someone else a profit margin.

That being said, I do agree that there is much benefit to not tying yourself to a specific employer before you're on property, but one does have to weigh that against their current situation.

Here's the most important question right now though: where do you live, or where do you want to live?

Are you Guard or reserve or something? "still short a couple hundred hours" is a long way to go. Are you at the front side of your military commitment? The RATP time should be no issue to accomplish unless you were sent to UAV's on your first tour or wound up with an hour deficit for some reason? PM me if you like and I would be glad to lay out a few options that may assist you. Not hard to get there these days and ANY regional will hire you if you are close to the mins.....no doubt. A mil pilot should be at 750 TT pretty easily early on.