The wiper, motor, and transmission is a ~$100 item at a "recycling" yard. And in case you are wondering, you can get the one piece gasket (assuming your unit has this) off your old one and on to a new (used) unit does not have the gasket with it. Carefully heat it up with a heat gun and it will stretch around the unit to remove, etc.

Rgds,
Chris W.
'95 E300D, 411K, on its second wiper ass'y

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