Had the same thing happen to one of mine earlier this year. You can buy the fabric, but I don't know if I would attempt to do it myself. I'm mechanically inclined and I didn't want to do it myself. I ordered mine from our local RV dealer and had them install it. It took them about an hour. It takes at least 2 people to do this, and it is done a lot easier working off of a scaffold than a ladder.
I have watched the local dealer do this and also awnings. There is a lot of work involved.
The toppers are easier than awnings, but it is still a lot of work.
Jerry and Janell & Westie dog Gus (Augustus McCrae)
Navy by record Marine by choice
2005 Bounder 38N DP 300 CAT 2014 Jeep Wrangler