Tam and all, Gran Sport Campagnolo pedals with alloy cages were definitely available in 1976, probably earlier.
They had a big flaw in my book as the main body was not pierced or cast with ports for the toe strap to pass through.
The cage was a simplified Superlight cage without the dimensional stamping as seen on the black pedals.
Light but I always thought less than one paid for as far a function.
John Jorgensen
Torrance Ca USA