It is my understanding that their is one licensed breeder - wildgrove that chips all it's animals etc.
I know of atleast 2 other breeders that are just private hobbyists who breed these animals. I know for sure in Queensland you need a certificate to verify where your animal has come from as to discourage people from taking these animals from the wid. It is also my understanding based on my conversation with Western Australian fisheries that outside of QLD a certificate is not required as they are non-endemic to the state.
My two guys came from a private breeder and not from wildgrove, but I do not live in QLD.