9K isn't a very reasonable life, is it ? I know they are cheap enough to replace but that's not the point, you'd expect them to last for years on any normal car.
I don't know if it would work with AVOs but when I refurbished my Europa several years ago with (supposedly) OEM dampers I replaced the rubber bushes with the metal/rubber composite bushes that you use for the front wishbones. They obviously don't have as much rubber in them but they are tough and stayed working until I bought the Protech dampers several years later.
Brian