The Humane Society in most cities offers low-cost spays and neuters. I had my kittens done for $20 apiece. You can use Google or a phone book to locate your nearest one.
I agree that contacting a rescue and becoming a foster home might be the way to go with all your cats.
Not as far as I know we're keeping females and males separate as I can't afford any more cats or kittens.I'm over my limit and just barely able to feed everyone. I'll look into it but I don't think I have anything to close. As far as I can tell Patch isn't pregs again, neither is my kittenless female.
The link I have provided performs spays for $15 per cat. They are in St. Louis, about 35 miles from you. Saturdays are the only same-day pick up. The other days the pet stays overnight. You show income for eligibility. Requirements are on the web site.
I know transportation is a problem for you, but if you can work something out on a Saturday, you could get your first mom cat spayed while seeking homes for the kittens.
I will look for shelters also that you may be able to foster with, or that might be able to find homes for the kittens.
Services in your direct vicinity are sparse as you live in a very small town.