I had the dealer replcae the hose in my 95 C220 since I just got the car 3 months ago. I don't think they replaced it with an original MB hose but I guess any high pressure hose will do as long as you have the correct hose diameter. I was watching the dealer when they fixed it to make sure that they do not break the O-ring (Thanks for the Info AKO).
MB owners need to check the hose from time to time. Since the hose is bent at an angle, this causes undue stress to the hose, hence, the crack.