When I lived in Vancouver, I dealt with a place in Surrey called Ace German. They had a yard full of nothing but Benzes. I got stuff like a power steering pump from them and a few other bits and pieces. They would let me take stuff off myself, or even help out. If a part didn't work when you got it home, they would give you another until you got one that worked (only happened once to me). I had them send me an instrument cluster and an exhaust manifold when I moved back to Toronto. Both items were reasonably priced and in very good shape when I got them. You can bargain somewhat with them too. Know the new price of whatever you want so you don't run the risk of getting taken. They don't know the new prices, they just throw a figure out that seems reasonable.
I don't own that 190e any more (traded up). Anyone in the Toronto area interested in a brand new sport cam for the 2.3 (from Bekkers)? Never installed it before selling the car.