I mail ordered mine. If you searched eBay, you will find some cheaper ones, and some sellers are in Canada. Don't buy used one though because these pumps are not designed to be completely santized, so if the previous person has whatever disease, it will remain on the pumps and spread to your child.
You can also rent a hospital grade one which is designed to be completely santized, but they are quite expensive to rent, and you shouldn't really need that.