Hi toorhax,
Unfortunately … I don’t have any particular knowledge about the European market (this site is focused primarily on the USA and Canada) so I won’t be able to help much in terms of specific retailers or manufacturers I’m aware of there but the steps involved in choosing a mattress would be the same and the mattress materials that are used in Europe would generally be the same as the materials in North America.
For those members that are from outside North America there is more information in post #2 here that should be helpful (except replace “Israel” with “Europe”).
Phoenix