In the past, I always used USPS for international shipping.
When you select “International Shipping” at the start of the online form, you just fill in the information .
At one point, it will ask about the type of product and description, then another in more detail.
There is a “drop-down” menu for selecting the “type” of customs, which I always selected one at random (probably the first one listed) - it sounds amateurish, but it always worked for me! My products always got delivered. I’ve sent to Taiwan, Ireland, Great Britain, Australia, Scotland and a military base in Saudi Arabia.