This may help some folks.
I wanted to buy an item from amazon.com. On the product page, there was a big note saying "This product does not ship to Auckland, New Zealand."
The item was not sold by amazon directly, it was offered by half a dozen marketplace vendors. They all sold through the fulfillment by amazon scheme and they were all listed with domestic shipping as the only option - no international shipping.
I put the item in my shopping basket and went to the checkout. I was expecting to see that the item would not ship to my default address and so I was going to select my youshop address which amazon also have on file.
To my surprise, I saw that amazon global shipping was on offer for the item and my Auckland address was accepted.
I ordered and the item arrived today - less than two weeks with iParcel which is faster than any of my other iParcel shipments.
I'm just posting this as a hint for anyone else, don't be put off by being warned about shipping, you may still get through when you go to the checkout.