Wayne, the "Campagnolo SR lookalike" Stronglight crankset is most likely a model 106 which came out around 1980. I have one of these on my '81 PXN-10. I've found that the best Simplex catalogues readily available are the Peugeot ones on Oscar Calander's site. They were pretty good at listing specs and usually had the latest models on their bikes.
Peter Kohler
Washington DC USA