I'm not familiar with late model Campy headsets, but I would suggest just biting the bullet and buying the correct part.

Usually if the race is designed for the same size bearing it will "work", but that does not mean it will be a good fit. It's important the the lower race creates a good seal to the frame cup to keep dirt out. It may have a thicker profile and mess with the stack height as well.

It's no fun knocking crown races on and off, and you won't really know if it's going to work until you assemble the whole thing. So why bother, just spend the extra dough (you would just waste it on something else anyway, right).

The headset is very important to the handling and overall feel of a bike, not any area worth skinmping on.