pom, thanks for the tip.
I've tried to look for a Norwegian supplier of this product, or similar products, and the closest I've come is a set of products from ewa-marine:http://www.ewamarine.com/english/e-cape.htm
These products protect against heavy rain and sea spray from almost any direction.
The "C-AFX for cameras with system flash" is available to me for the equivalent of approximately 225 dollars (plus freight and taxes).
Jeez, for that price, I can get the Kata rain cover and a handsomely big extra memory card from B&H*! Plus mittens!
So I really mean it by those thanks, pom!
* The cheapest shipping method from B&H for the Kata rain cover is USD 27.50. Add 25% sales tax to the sum of product and shipping, plus a fee of approximately 20 dollars from the postal service for handling customs, and it's not quite cheap anymore. But it sure beats that ewa-marine in price, if not in protection.