I would think that with the design of the Super/Reunion, the only place where the small difference in shaft diameter would come into play, is that the Super/Reunion actuator will have a hole slightly larger than the Wico shaft. As you said, electrical tape should fix that.
Too bad they won't swap the other way, but the larger Super/Reunion shaft won't fit through the Wico grommet, and without the "step" found on the Wico shaft, it wouldn't work anyway.