I've seen IIRC quite detailed repair instructions posted on tinternet, on a forum similar to UKC, they were a copy of an article originally published in a Caravan/MH magazines a VERY long time ago! - May be worth Googling a bit to see if still to be found.
If nothing else, they prove that the flyscreens are repairable, if you can work out how, rather than a certain scrap and replace in their entirety solution!