If your snake eats frozen already, why not just buy frozen rats or mice from an online dealer? The animals are healthier than those you can find in a pet shop and are humanely euthanized prior to you purchasing them.

Having only 1.1 rats means that the male will almost always be alone since you don't want the female to be constantly pregnant(hard on her and the resulting offspring will suffer for it). And the female will need a buddy while she is resting. So you would need 2.2. It's not possible to save money when you're breeding rats for one snake. If you had 5-10, maybe, but not one.

It's much more economical to just buy what you need online and have it shipped to you. I can get adult mice for 45 cents apiece from Big Cheese Rodents and their mice are always healthy and chubby.

www.bigcheeserodents.com
www.themousefactory.com

I do not recommend RodentPro, ick.