Best bet is to find a w124 at the junk yard, snip out that whole rear quarter skin and swap it onto yours. Assuming no damage underneath., doesn’t appear that there is but never know. Grind and bondo the welds then painT

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1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero