For a system that sold around 2million units, there seems to be quite a few variations and revisions. I had a REV M board at one point, and a B,C,D, J... Then yes, you have CBS and Canadian models. Really, when we get down to it, some systems that we own may have only had a 4digit run(aside from obvious ones like prototypes and review units) before something was changed. My first coleco, brand new in the early 80s, had some kind of woodgrain sticker. Still to this date, I've heard about 20 different theories on this and used to think people peeled it off if I saw one without the faux wood. The funny thing is, most CV enthusiasts have this experience with odd revisions in something from coleco, whether it be something on an accessory or the console itself.
But once you get into the foam box variations...........lol.
I personally don't think there are only two. I just don't have the slightest clue as to how many.