If it's a product you want to protect, then you really need to sort out your patent before even thinking of discussing it with anyone. That should be the very first thing you do. In regards to sourcing someone for the work, I would suggest speaking with Elizabeth from IMEX who are a Chinese sourcing agent.
They will have the contacts to facilitate this type of procedure for you within China. You can get in touch with her here Link hidden: Login to view
Good luck with the project.