Hi Arno, welcome to this forum.
In France, try the Fuji repair facility first:
Service Après-Vente FUJI
2 avenue Franklin, 78186 Saint Quentin en Yvelines
Tel.: 01 30 85 65 43
Fax: 01 34 60 57 45
If Fuji cannot help (very likely, because these cameras are not officially supported), you could try
Formosaflash (I have heard nice things about it) or
Nikken Techno. The shutter in the Fujinon lenses is a plain Seiko 0 shutter, which is very commonly found in Japanese MF cameras (Mamiya, Bronica, Kowa). Almost any professional repair facility should be able to deal with those.
Cheers,
Sebastien