Try 1st class registered mail from USPS. Don't bother trying to insure it. It's more of a hassle that it's worth. Besides after a year the knife is still missing and the issue is still open. Recently shipped one and my daughter took it to the PO, just plain 1st class, she tried to save me money, and it got there in about 12 days. I worried and prayed day and night.
Custom duty fees to the buyers can be considerable, also check their laws, you may be sending something that is different than they can possess. That's a whole other story.