Hello i am a Canadian on a working holiday visa in New Zealand.

I have a flight for Beijing on the first of April. I am based in Te Anau in the South Island. Can I ask for my visa by post? If not, what is the best way for me to get it.. Knowing that my flight leaves from Christchurch? I keep on reading that Christchurch doesn't do application for foreign people. Only for New Zealand passport.

Thank you
Julie