This won't be much help but not sure how you would replace just the tenting roof. It is stitched to the sidewalls isn't it. And I do not think there is anything you can put on it that I am aware of. You may have to replace the entire section. There should be a label somewhere for the tenting manufacturer. A common one is TJ Snuggles. My label is on the tenting material just inside the door.
HTT: "EscapeII" 2016 Shamrock 23WS (current)
PUP: "Escape" 2010 Rockwood HW 277 (gone)
TV: "Bruce" 2011 Dodge Durango V8 Hemi Crew
Just us gals (me, Sis and our daughters)
Traveled 19520 miles and 209 nights in 7 years and counting