Changing the interior trim on E Class coupe - possible?

I'm on the usual quest of trying to find a used car which ticks all my boxes. This time its an E Class Coupe E350 (2009). Of course its impossible to tick all the boxes so I'm figuring out what my options are. I was wondering whether there are companies you can pay to change the trim - e.g. from the standard brushed aluminium (which I don't like) to the black ash or burr walnut, which I do?

I suspect a Merc main dealer would love to do this for you if you would just leave your wallet behind....

Suggestions?