W/C126's came with leather, MB Tex or velour. I had all three, velour is awesome and was a no cost option almost no one in the US got.

The interior on that car is either aftermarket or if you can run the cars vin might have been custom ordered. MB did special order stuff for very good customers, some research would be required. If you pull the rear seats you should see tags if they are from MB.

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2006 CL500
2009 C300 4matic
1969 280SE
2023 Ram 1500
2007 Tiara 3200