Hi Blake
Contact NZ Customs and MPI Biosecurity. You are basically importing animal products not for human consumption.
When I brought back a shoulder mount and a skull last they were only interested in 2 things. Biosecurity risk to NZ Agriculture and if its a protected species. I had the trophies on the same flight with me so I let customs know what date and flight I will come in on just to speed things up. The trophies been done professionally and gave them a good clean again before preparing them for transport. Biosecurity took everything for inspection which was done in 20 minutes.
I had a whole bunch of paper work from country of origin they took a copy but needed it mainly for customs when I was leaving EU with dead animal parts in a box. I had declaration from Conservation Dept saying it wasn't a protected species, one from state Vet saying that the animals were disease free, and one from Wildlife management stating that they had been legally harvested. So check what do you need on your end to export animal products.
Cheers BF
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