Wouter,

You could go to Cathouse1.com and maybe contact Mark Biggers. Those guys up there have a pretty good size fleet of Nacra F17's, and I believe they are the ones that started this F17 business in the first place. His response may be a little slow though because they have Nationals going on up there this week.

Tom

ps. Don't forget the 1 after cathouse or you may end up at quite a different type of site..............