KA in NZ the adoption doesn't seem to be final in some (all?) cases. I know of a friend of mine who had a child when he was a teenager and the mother decided she couldn't cope and it was adopted out to my friend's uncle. Then after them having the baby for a year the mother decided she wanted it back right before Christmas. To make it worse the family had a 4 year old and she kept asking where the baby had gone and would she be taken away too
I think there are some international adoptions that don't require you to travel to the child's birth country. I would recommend researching it. CYFs have information about countries that NZ partner with for international adoptions. You could see if any of those will let you adopt without traveling.
I started researching it as I also would love to adopt but I have put it on hold now I have a baby to look after. Hopefully someday soon.....
Anyway best of luck - let us know how you get on.