Here's another piece to the puzzle. The subject catalogs would appear to be pre-1966. An announcement appeared in a French cycling industry trade paper that Cizeron would be manufacturing 1966 pro team bicycles under both Anquetil and Geminiani branding. The announcement actually shows two pro teams (and a 3rd amateur team) but the jersey description is the same for both teams, though they don't mention sponsors. Maybe they were considered A & B squads? I'm not quite sure of the rationale behind it, but it corroborates with the the observation of two brands being used by the 1966 Ford-France pro team and more importantly, identifies the manufacturer.

Cizeron was a full range manufacturer based in St. Etienne, so there's a good probability that they also manufactured the complete lines for both brands. I found another trade paper announcement from 1971 stating that they were still manufacturing the Anquetil and Geminini brands at that time, in addition to their own brands of Rochet, Olympique and Campione. They also contract manufactured Jeunet and were responsible for the French manufactured Fransesco Moser bicycles that pop up from time to time.

So, there is evidence supporting Geminiani being manufactured by Cizeron for 1966 and 1971 and probably the years between. That suggests the Gitane clone catalog is pre 1966.