The company that creates my rear window spoilers (
link), also produces a Porsche style fan shroud for the type 1 and one for type 4 engine. Both are for the 260 mm Porsche fan.
I want to see if people are interested in this fan shroud. The price is 90 euros.
They are made out of fiberglass. Maybe a carbon fiber one is possible too, I'll have to ask.