Whereabouts are you? I have a hunch that Ricki at Pankhurst Cycles in Pangbourne might be able to help if you’re in a hurry.
I bought a NR rear and an SR front mech off him only a few weeks back and he seemed to have got some stock of older Campagnolo kit in. Might be worth a call?
I know Rikki, we go back to the time he was working at AW cycles in Caversham ! ;-)
I will try calling him and depending on his price ... I was trying to collect all missing bits on the cheap side of things as ebay prices seem to go over the top
rear derailleur would really help me ....!