I went to order a cable for a Self Propelled Windtunnel in the shop last week and discovered they are no longer available. Even the aftermarket ones have been discontinued as well. Another issue I've been noticing on older units is the nub on the transmission cracks off and makes the cleaner head sink to the ground. That plastic nub is responsible for carrying the weight of the head from the adjustment actuator.
Just figured I'd let people know before they snag one of these and discover the bad news. I can't imagine there aren't shops still out there who stock them, but that won't be for long.