Interesting question, but I don't think Canon pursued this market during most of the RF period. Canon did very well selling to their home market, and through the Military Post Exchange system into the 1950's. When they entered the US market, their emphasis was on cameras like their late Barnack-type, and the huge success, the Canon P.
The closest thing to a pro camera, IMHO, would have been the model 7 and the later 7s, where they featured the unique f0.95 lens. That lens was extensively modified then, and later, to work with the M3 and later models of the M-series. The same lens was also produced for a number of years for the TV and movie industries, with apparent success. It seems to be still a cult favorite, and is a better lens than its reputation.
So, in my considered opinion, the 7s, or last model 7sZ, would probably be as close as they came in the RF era.
Later, of course, they emerged into the SLR's, with the several models of the F-1, another story, for another forum. That was also when they produced their first motor drive, AFAIK. They did make winders for the Barnack tyhpes, and the trigger wind, like the VI-T.
Their lenses were practically all of high quality, and are mostly bargains in today's market, compared to the Leica, especially.
Brian Sweeney, who is a Nikon collector, and quite familiar with many things Canon may have opinions that he will share. Of course, Peter Kitchingman, who wrote the lovely book on the lenses and Peter Dechert who wrote the seminal book on the cameras are also major figures who, hopefully, will give us some thoughts.
Harry