FWIW, MB dealer parts departments don't take deposits on key orders. All orders must be paid in full at the time the order is placed. In the case of the older cars there's nothing to order so it's not possible to prepay.

After spending nearly my entire adult life working at MB dealerships I can tell you that the way to get results IS to complain to MBUSA, and the more complaints they get the better the chance that they'll take action......