I am in Leicestershire, England.
I don't have any mice right now. I am an ex breeder and just "dipping my toes" as it were, back in the water.
I was, like you, finding it difficult to locate fancy mouse breeders in my local area to start me off, but I met a guy who told me to join this forum and speak to certain people. I did, and as a result have met lots of nice people and have some mice coming my way in a few weeks.
Maybe someone else on here is in New Zealand and can help you, but as I'm so new I cannot advise. I know someone will post you soon and help you out though.