If you live near the water you should be able to locate a marine canvas dealer. I have found the dealers near me to be quite helpful. When I mentioned I was covering a sea kayak they were very helpful and interested. I guess because it was something new and different for them. Otherwise you can obtain #10 duck via mail order through www.pearlpaint.com . They sell it quite cheap and in a large variety of sizes. I'd stay away from anything colored. Who knows what was used to color it and how it will affect the waterproofing properties.