Let's say I'm a manufacturer of widgets based in the US. I have a product that is tested in the US, but I'm not terribly interested in the European market. As a result, I do not submit it for independent CE testing.
However, recognizing that I'll get some European sales, I submit my US testing to European authorities, citing to my US testing and the appropriate trade agreement. CE recognizes my testing as valid, and in conformity of the appropriate CE testing, and grants me a CE certificate.
And I'm simplifying like crazy here. For a manufacturer, this is a long, drawn-out process.
Hobie US may already have a CE certificate for US made Waves. That's why I suggested you contact mmiller. He would probably know who to contact within US Hobie. If that's the case, that will be all you need. Second approach would be whether US Hobie Waves are made to the same specifications as European Waves.
I'd also contact <email@example.com>. This is the business affairs section of the US Embassy, and part of their job is to assist in exporting and importing to the US. You might also contact http://www.europages.co.uk/CARGO-CENTER-SWEDEN-KB/bch-EUR-SWE013193-00101-25/company-information.html
which specializes in importing vehicles into Sweden. I've never worked with them, but I'd contact them and see what sort of cost they're talking about to do this.
A CE certificate is just one part of the import/export process. It's hard to do this without hiring an expert.
Best of luck,