Jeff, I don't have a clue what a 7000 series frame is. Could you post a photo of it, or at least post the serial number?

I think the bolt you need is Campy p/n 3456, and the pivot bolt on the Gran Turismo deraiiler I have is considerably longer (the derailler body where the pivot bolt goes is much thicker than the Rally body), so I don't think it will work.

Again, you might try your LBS to get the right bolt, or some of the mail order businesses that specialize in small bike parts.