During the March 2018 sale, it was possible to order the Torturer of Dol Guldur 1/6 scale statue from any location, with local shipping, as if it were in stock in the local warehouse, even though it wasn't at that time.
Weta took all the orders, and then when it was convenient for stock to be moved to the local warehouses to fulfil those orders (July), the statues were shipped to customers.
This worked very well and meant I could order the statue without having to pay the shipping costs from New Zealand. All it meant was I had to wait a few months to get the statue, which is not a problem. I'd rather get the items later than not be able to get them at all.
I would venture that the vast majority of collectors of Weta pieces feel the same, and would have no problem with waiting a bit longer to receive their items if it means they can order from their local warehouse and not have to continually be faced with the message "Shipping worldwide from our NZ warehouse. SOLD OUT in our EU warehouse."
My suggestion/feature request therefore is that Weta make all products which are not completely sold out available to order worldwide, and that they just move the stock around when its convenient (i.e. when a large number of items are on back order and can all be shipped to the appropriate warehouse together).