he front stock springs on my 2006 C55 AMG W203 are manufactured by Eibach.
Frankly, given the experience of independently changing four shocks and springs on this vehicle, we could establish an entire forum dedicated to acquiring the appropriate springs for your Mercedes-Benz. It is a perilous situation.
I was fortunate with the front, since the majority of the component number, the 'legend' AMG (which adds 50% to the retail price), and the color marks remained discernible.
Neither Eibach UK nor Eibach Germany would provide the items to me; I had to get them from MB, and the pricing was satisfactory, to be honest.