That is a real beauty. Can you confirm the date code on the movement?
16AE2 I think this is it
That is the movement model; The date code should be 2 digits; a letter and number. 1976 would be "N6".
It is a N6
I can't come up with a model name in the database, but here it is! A possible name may just be "Bicentennial", with subject watch being a variant letter, currently unknown.
wow thats cool i dont think its every been out of the case but just to look at. The chain is a link type not a snake type
Based on the watches shown in the referenced ad; it appears your watch chain is indeed a replacement.
Well I guess I will be looking for one
Found one on Ebay
The movt is the Unitas/ETA 6498, a common movt for late stage pocket watches like this. The Lepine version is of course the 6497.
I was at Tourneau in Vegas in 2009, and Panerai was using the 6497 at the time. The originals used the Rolex version of a Cortebert movt, and more rarely, an Angelus ebauche.