If you get to downtown Vancouver check out Dressew on Hastings. I doubt they have a website but you can see reviews here.
http://www.yelp.ca/biz/dressew-supply-vancouver
They do not take credit cards, but I think they take debit now, otherwise bring cash.
You will have to hunt around to find things. I know they have quilting fabric, I am not sure about the quality.
It is the sort of store where you can find just about anything, if you look long enough.
It is near the Downtown Eastside, but I have always felt safe and comfortable there, even when walking several blocks to get there.