I don't think you really are required to take a whole lot of math to be able to teach it anywhere below the college level, so you'll probably be fine. I'd want to make sure you at least get up to Calc I or II so that you could teach it if you had to, though -- but that's just my outsider's thought on the matter.
Do you know any current teachers at this level, or would you be open to wandering into a random school and asking to meet with any when they're available? I'd think they would be an excellent resource on at least what they did to get there. I'm sure they know all about the shortage of math teachers, so they might well actually be happy to help get even one more person into the classroom.
Just beware of those science teachers, because they'd also probably love to steal you to help with their shortage as well.
