These watches get discussed from time to time on this forum: https://omegaforums.net/threads/opi...al-285-lecoultre-cartier-and-universal.15000/ https://omegaforums.net/threads/rare-compax-model-chrono-made-for-cartier.13836/ Most are met with a skeptical eye. I recall that, for a price, Cartier will search their sales records to help establish provenance.
At least the handset does not match the dial (hour and minute hands too long, subdial hands to short), so I think it is a put together watch, but I am not an expert on these.