The Super Champion front derailleur is not only missing it's clamp but
also -as far as I can see - the limit plate. The limit plate adjusts the
sideways throw of the cage and is held by the screw that sits in the bronze
body.
I have recently uploaded photos of this type and other front changers on to
Classic Lightweights.
http://www.classiclightweights.co.uk/
The limit plate is easily fabricated and I could do a drawing of mine if the
purchaser sends me stamped adressed envelope.
Mark Stevens Evanton Scotland