If you contact me I can put you in touch with my manufacturer and rep from China.to see if they can fill your needs. I started out with a US manufacturer, but switched because the savings is very substantial.
We are working on promotional production sourcing in China for many years and we are more than happy to make a pre-production sample based on your prototype. Please let me know your email or phone, I would like to talk with you soon.
They are great sites. Especially when you are not sure where to start. It can get a little tricky when you have a particular product that you want made instead of buying what they already make. Still, it is an excellent way to make contacts.
Two word of advice I would give:
1 - Make sure that you are crystal clear about what you want. Chinese suppliers really don't like quating that kind of uncertainty. Prototypes/samples are really good. Sometimes proper engiring drawings are better. It depends upon the type of product
2 - Have a good idea of the numbers that you will likely order. If you can talk business right from the start they will take you more seriously.
Good luck with it.
You can find OEM manufactures at ww.globalsources.com. You can also get advice on sourcing direct from China suppliers (it might be even more cost effective for you!) there and at www.smartchinasourcing.com. Good luck!