They're called Wellnuts and lots of places stock them, although none of them seem particularly cheap. I saw some at Riverside Motorcycles in Northampton, although that's probably not going to help you in Switzerland. The usual mail order folks, Busters, Demon Tweeks etc should keep them though
I don't know the current price of them because I got a complete set of new ones included in a kit of Pro-Bolts aluminium fairing screws, they look quite nice so you may want think about replacing the screws as well. I can't remember how much I paid for them but they're on the Pro-Bolts web site
In my experience though, the still work alright even when the grommety bits look tatty, so you may have nothing to worry about.
Having said that, they make getting the fairing off a complete pain in the censored, so I'm looking to replace mine with Dzus fasteners.
[Edited on 22-5-2004 by Jools]