Perhaps I wasn't clear in my original post. The key I am referring to is the one that holds the clockspring for removal. You can see it in the link below. Would you buy the OES part over the OEM to get this tool? I don't want to regret the purchase. Any help will be appreciated.
http://www.carparts.com/details/Mercedes_Benz/C320/OES_Genuine/Turn_Signal_Switch/2003/W0133-1891541.html?TID=froogle&cpoegetusisw03mercedesbenzc32020032003oesgenuinew0133-1891541989140

Thanks!