Well, if you want to get started with "rattery" breeder rats, you have to jump through their hoops and "mentor" yourself with a reputable breeder. do all kinds of research and who knows what else before they trust you with a breeding pair. Then any litters have to be adopted out using the same ridiculous adoption contracts, etc.
If you are dead set on the rats from one of these breeders, you would basically have to adopt one as a pet and lie. Lie about everything including your name and address. You'll have to do this twice with different breeders because they won't adopt out a male-female pair.
Or you could find a feeder breeder that has the rat types you want, or buy from a pet store and take your chances with any possible negative traits. Petsmart has blues and dumbos and rexes and other more rare types on occasion.
I went through the same thing at first, wanting the "breeder" rats but their contracts were ridiculous and I just bought from Petsmart and bred them. I now have blues I've bred myself and am outcrossing them with a dumbo to eventually get blue dumbos. I keep a bunch of the rats as pets and breed them occasionaly. The pups make the best pets because I am able to handle them and socialize them from birth. The surplus pups get euthanized and frozen for snake food.
The only real problem with buying from a pet shop or feeder breeder is if they have respiratory infections when you get them. They can easily infect the rest of your rats, so it's best to get them all at once or if you do get them separately you need to quarantine them for at least 3 weeks in a different location.