The folks at MEC used not to sell them because they could not find any company to recycle them, but sometime this summer they told me they would carry them in the near future because they had found a recycler. Not sure what has happened since (http://www.mec.ca).

Of course carrying a pump adds to the bulk, but it certainly reduces inconvenience and increases safety when you're on a low-traffic road, 50 km from home, with a second or third flat tire and no more CO2, or after you've helped someone on the road and then get your own flat. Murphy's law says that on a given day you will have as many flats as the number of spare tubes you have and patches you have + 1. Also applies to CO2.