If you know anybody with a lathe or have an engineering shop near you they might be able to put that cap in their machine & by the looks of it, tidy the burr up so it's hardly noticable. It would certainly look a lot better than it does at the moment ! Depending upon how much material is taken off that cap you might want to think about having the other undamaged one made to look the same so they both match.
I'll do that if I can't find one to swap. There must be crash damaged forks where the cap survives - I was hoping that would be easier than machining the marks out of this one.
It turns out these are still available from Ducati, Motorapido have ordered one for me https://www.stein-dinse.biz/product_info.php?products_id=126228