Campy did make headsets without the annular groove; in particular, the early Pista ones. Picture below is from their 1967 catalog. By 1982, the Pista headset had the groove too. The Bottechia may (if it's not a track bike) have a steerer cut so that it needs a lower-stack headset, and the Pista is just that. On the other hand, you show a lotta thread above the top race (unless photo is with no bearing balls in the headset).

Note that your locknut does not match the one in the catalog illustration, though. I would expect that in 1967 all the headsets would have been steel, rather than alloy. What is yours?