Storms, I think your problem is more likely to be on the NZ end rather than on this end. You might want to post a question specifically referencing NZ firearms laws and someone may have an answer for you. Getting it back to the States . . . I think you could fly back with it if you had an appropriate locking case. The one document you'll need is a US customs declaration, which you can get before you leave (probably when you ship it) to verify that it's your gun and you took it (or shipped it) out of the US. That way you should not have any problem either bringing it back to the States or shipping it back, and you won't have to pay duty on your own gun.
