Philippe,
I got my SL in the US, and found that it is easier (and a lot more cheaper) to buy classic MB parts in the US than in Europe.
You need only to be carefull with the reference of the parts, in order to be sure that you order the good one (on the internet).
In France, SLS is well known, but you can also ask Mercedes classic through your local MB dealer (in Paris "Mercedes Lonchamps"). I have also found "Niemoller" (
www.niemoller.de) in germany, but some parts are also available from general discounters like "Oscaro" or "Webdealauto".
So, get on the internet, and do your shopping !
Jean michel