Confession time. After reading accountantpete's post, first chance I got I took another look at the shifters and I discovered I had the left hand one trying to change the rear mech
I don't know why, I just think I tried it, found it had numerous clicks and assumed the other one was for shifting chainrings.
Anyway, I have counted the clicks and there are seven so I assume that means these are 8 speed? It would be fine with me if they are, I am building up an old 531 frame. At the moment I have a set of old wheels fitted with Shimano 7 speed screw on block and a Campag 980 mech. It does change alright'ish, but it does seem to skip a gear sometimes when going up or down the gears. Thinking about finding a slightly more modern rear mech, this one does not grip the cable tightly enough, as it slips through the clamp. I am having to wind it right around the clamping bolt to stop it slipping and it is not doing the new cable any good at all. Were older cables slightly thicker? Maybe the groove in the mech is worn a bit, as when the cable is in the slot it is almost flush with the face of the clamping surface so the nut and washer don't get much of a grip.