Transpac lists 200, CFI,II,MEI proffered. I know people who have gotten on there with around 50 dual given but that was knowing some really good connections.

There are hundreds of CFIs on the street right now with 1000s of hours of Dual Given (wow, that line sounds familiar) so there might be some stiff competition. There are also an equal (if not greater) number of wet CFIs on the street clamoring for a job so even having a couple hundred hours of dual given should make you competitive.