Hello vintagerando,
The usual difference between a TDF and a Super Corsa was the Campagnolo headset on the Super Corsa.
The Stronglight headset in your photo looks oddly overstacked.
Super Corsa steerer tubes were longer than TDF steerer tubes.
Check the stack height on the steerer tube, a Super Corsa would have a height of about 40mm or so (estimate).
the extra spacer to there to take up the space formerly occupied by the mafac centrepull hanger.