Join (or just ask?) the Lotus Seven Club of Switzerland -
http://www.lsos.ch/pages/historic-register.php
I was a member a while back, good people. Run the St Moritz do every July, 150 Sevens attend, typically. Also I have run in to (so to speak!) various kit car types over the mountain passes. So yes, there are kit cars in Switzerland, lots of them.
Kind regards
Anthony