I stand corrected!
Well I was parked next to an older SLK recently and decided the belt moulding on it looked like the belt moulding on my Crossfire. Then I saw a thread where someone had installed door cards on a Crossfire from an SLK and the fit was perfect so I ordered a belt moulding for an 03 SLK 320 from a MB parts supplier on line. It was about a hundred bucks and fit perfectly
https://www.pelicanparts.com/techart...eplacement.htm
Is the the part that you are referring to that you were in need of?