Hi Sterncactus,
General nurseries here (Sydney) also sometimes get them as part of a mixed lot of cacti. They hate overwatering, so often end up dead - you need to get there quickly when a batch has come in. They are difficult to mistake for others cos the hair is quite cottony and coarse, if that makes any sense. If you are still having trouble in a month or two let me know and I will try to pick up one or two for you and post them up. (No guarantees cos they are not always in stock. I think they are Paradisia plants or else from Hamilton's World of Cactus.)