Do you know what difference is with c record and chorus
As in where did they sit in the hierarchy? In which case Record / C-Record has always been more expensive than Chorus.
C-Record (Corsa Record) is, like much of Campagnolo's naming, used slightly inconsistently which makes every item on
eBay a C-Record... unless it's unidentifiable in which case it's always a 'prototype'

It's the equivalent of Dura Ace over Ultegra, I guess... in the periods in which they co-existed.
If you go back far enough of course, Gran Sport was Campagnolo's top-of-the-range, over Paris Roubaix and Cambio Corsa!
As for the actual differences between them,
this article is both worryingly detailed and very helpful. I'd pay more attention to the levers as an indicator than the hoods, as these are readily available as replacements.