As far as I understand OSK's logistics, Kit ships them to a United States re-shipper. The most recent package I received from OSK was shipped from Washington state. That re-shipper pays the import fees assessed by US Customs. Now the 10% tariff will be added on to those fees. I would imagine that the re-shipper then bills OSK to recoup those fees. Normally those fees are already baked into OSK's price, hence why the shipping fee is included in the OSK price.
I have no idea how this will work for items already purchased, if/when tariffs are implemented. If the incoming US shipment of Legolas costs 10% more, that's a huge cost that will need to be recouped. Is OSK going to eat that charge, or will OSK have to reach out to customers and say "Due to tariffs, the balance due will now be $535 instead of the previously stated $480"?
I know a bit about this as I dealt with importing figures from China into the United States. We had an agent that drove a truck down to the port, picked up the cargo, then delivered it to our warehouse. A few weeks after we received the shipment, we received a bill that included their delivery fees and any associated import costs/fees. We overnighted a check to them to make sure the bill was paid promptly. So, in that scenario, our agent would've added the 10% tariff onto our bill for delivery services. Those fees are just part of the cost of doing business, it comes out of our margin.