Thanks for the replies The seat post size is 27.2. I took the forks out and there is no markings in the steerer tube at all but drop outs are Columbus. Has another Reynolds 501 sticker on the fork blade though and a lot of glue residue from many stickers that had been removed. Maybe the previous owner just liked stickers?
Most running gear is Campag, though has a Shimano 600 rear derailleur.