Just in case you end up finding them, I figured I'd give you a few tips I learned through trial and error. I can't own them here in CA, but when I lived in Denver I bred them for years.

They breed much better in groups of 1.3-5 vs 1.1-2, and swapping out males like you can with mice/rats doesn't usually work, you want to keep the males in with his females at all times. When your males or females are getting older and close to needing replaced, you should just grow up a babies produced by that colony with them the whole time. 1.1 would almost always cannibalize young, perhaps because they were failing to thrive because not enough moms to feed the babies on the right cycle. Given this very different way they breed and raise young, you need to plan how you house them differently and carefully plan ahead to get the right numbers because it's not so easy to just not provide a male to knock up the females if you have too many and put him back later.

Best of luck finding them.