I have always sought out booted winter blades. Since the open frame is covered they do not clog with snow and ice and work very well. In recent years however the "beam" type blades have become widely available in all sizes and also offer the non-clog feature since they do not have an open frame.

There is nothing special about MB wiper blades or their attachment mechanism. I source mine from any auto parts store (or WALMART) and suggest you do the same. If it is important, any auto store stocks Bosch blades.