I understand that you can now get 3D scanners. But not quite down in price yet and not sure about accuracy either.
If able to scan the area for the fairing (different from plane to plane), one should be able to do something nice in SolidWorks or Fusion360 and 3D print it.
May not be easy to print, though. Will probably need a lot of (wasted) filament to make temporary printing supports.
Finn