Suggest for you to call Digikey and ask them. They should be able to help you out.
Respectively, you are wanting to build in China? The contract manufacturer should be able to purchase the goods on your behalf and add to your invoice. This may be much cleaner. We went through nightmares with assorted duties and taxes when attempting to drop ship goods from Taiwan / USA / Canada to Shenzhen. It is a double-standard over there. Even though the goods were paid for properly during IMPORT to Canada -> then we paid local overhead, after wanting to send back to Shenzhen for assembly - got taxed again. Not happy with that.
Respectively, are you sure you cannot source the same goods within China? That would be easier on your pocketbook I would think.