As far as I've been able to determine, all of the Atlas machines have always been a shade of machinery gray, except possibly some sold to the War Department during WW-II that were OD.. I'm not so certain about the color of some of those sold in England under other names such as Acorn. Some of them might have been a bright green.
Not that it matters, but "battleship gray" is a figment of some Hollywood type's imagination. In the real Navy, it is called Haze Gray. As in haze gray and under way
Anyway, the gray gear cover looks much better than that blue thing.
Robert D.