Some prices I have seen in the past:
Tire Carriers usually cost between $60 -$180
Rear hatch usually cost between $100 - $260
These are purchase and local shipping prices inside Japan, international shipping I have no idea on that cost.
The Tire Carrier is small enough and light enough ship through USPS if you could arrange it, but the Rear hatch is too large to ship through normal USPS mail.
A friend of mine imports cars and parts to the US from Japan, you could ask them how much they might charge to throw in a rear hatch and a tire carrier to one of their containers.
Mostly they do GTRs/S13s/Silvia and RX7s but they also transport body kits and such.
The Company is Infinity Imports International
https://www.facebook.com/Infinity-Imports-International-943180122388331/