We aren't going to show these rabbits, just looking for a fun variety of colors
Be aware - if there are kids involved, they will get attached to the "pretty" ones, and there isn't that great a market for pets the size of a NZ. If these rabbits are being raised for meat, it's easier to not get attached to the plain white ones.
Chocolate isn't
supposed to be in New Zealand bloodlines, but we all know about things that aren't supposed to be there, don't we?
If this breeder is working with Blue, then the Blacks might be carrying it - if pedigrees aren't available, the breeder should at least be able to tell you if they have Blue relatives.
Red doesn't look like it, but it's an Agouti pattern color. A good New Zealand Red is a combination of Agouti, Non-extension, Wide Band, and Rufus Modifiers. If you aren't a genetics nerd, that may be Greek to you, but let's just say that you'll most likely wind up with a lot of "not Reds" if you breed Red to any other color. Chestnut is the most likely outcome, but a Black could be carrying Steel, so you might wind up with Steels, or simply Blacks that are actually Steels (but we don't
really want to get into that, do we?)