If your breeder has 42 puppies for sale at one time you probably dealt with a broker, not a breeder. Besides the obvious problem with her bite, Squishy may have other genetic issues she could pass along to her offspring. Since many genetic problems don't surface for years, it isn't safe to breed a dog with an unknown background.
I know she is your dream dog so she is perfect in your eyes no matter what the vet may say. Get her spayed and just enjoy her as a wonderful pet.
Here is some information about parrot mouth and other bite problems in dogs:
Malocclusion: Misalignment of Teeth in Dogs