In 2014 when I traveled on The Canadian, I remember the list being 8-10 varieties, all Canadian beers. Let's see how my memory is...Molson Canadian, Labatt Blue, Kokanee, a couple from Granville Island Brewing in Vancouver, a couple from Fort Garry Brewing in Winnipeg.
That makes seven, but I am pretty sure I've missed 1-3. As a beer lover, I managed to try them all once in the course of a four-day journey and enjoyed that each was served with a glass, if desired. Not a plastic cup, a glass!
As stated before, the wines are all Canadian as well. Take advantage of the free beer and wine tasting events in the Skyline car. A fun way to try most of the options and concentrate on (and pay for) the favorites for the rest of your trip.