Mikael,
I spent several hours scouring the web for this part. The closest I can find is a SINGLE reference but the part looks correct (less the screw holes for mounting).
See here:
http://www.fiatalfadealerparts...lamp-washer-jet.html
You can hopefully repair yours.
Also, I looked through all of my Longchamp images and can't find a single other car that has these washer nozzles or your unique windscreen wiper arm assembly. Perhaps your car was used as a test car for new ideas at the factory?
Good luck!
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