Why do you need a new cover? If yours is like mine was, with cracked and shattered piping but otherwise in good condition, just remove it, undo the stitching, remove the piping, and sew it back together using the same holes. Then you can reinstall, and it's good as new. Best part is, it's original and matches the rest of the interior in color, sheen, and wear.

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08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280