Not available anymore, anywhere. The Sterling canopy seal currently is a simple D style rubber seal which is available online through suppliers like Steele Rubber Steele Rubber Products - Peel-N-Stick Ribbed Hollow Tall Bulb - 10 foot
Window seals are usually just as simple, peel and stick foam rubber flat stock, also available in local hardware stores.
Trim-Lok has a wide range of plastic or rubber seals and trims for use as a drip edge; window seal, trim or molding; rubber gasket or tubing; PVC trim; and more!