We bought "Sunbrella-like" material on Ebay and have been happy with the quality so far. Search "Marine One Outdoor Fabric" and you'll see it comes in a bunch of colors. The seller I bought it from was Textile Specialists and they sell sunbrella as well, just not in a ton of colors. We ended up paying $7.50 a yard I believe. Much more manageable as we're on a serious budget.
So far I've made a dodger and sail cover from it. You can see how it looks here