We found a manufacturer in China through Alibaba and that has been successful. It is very similar to something they were already producing, just required some design changes...nothing complicated
We had a 3rd party quality control person inspect the first few runs of product at several points during the process.
As a side note, Before we placed our first order my partner flew out there to see the factory so he could make sure it was legit and establish himself personally with the account exec. This was based on the recommendation of a family member who had goods manufactured for years in China. I get the sense that a personal relationship is still highly valued.