This seems to have sparked a lot of interest from you Campag "heads" out there.
If this helps. The thing came to me in that box, with that plastic support. It was part of a shop clear out, and I have no reason to suspect it has been reboxed. The box has another stick on logo on the otherside. A more modern, blue scripted campag one, with the batch control number. (there goes $50 off of the ebay price!).
The headset itself has no < C > markings. No hidden markings other than the size and place of origin under the lock nut. It is so fresh there is even a bit of "Flashing" where one of the holes was not drilled right through! (Ha got my ebay $50 back).
I hope that helps.
On the subject of early Campag bits, a few days ago I sold some early, "flat" campag cable clips on ebay. A few people from the list asked me if I had more. I have now, set of two top tube ones are $14, including airmail. My ebay set fetched $78!
I also have some of the very nice Campag twin cable guides, with the built in pump clip. part number 631, page 80 of the English version of catalogue number 17. these are $22 each
Regards Martin Coopland, does 8 degrees C constitute a warm Scotland?