The last I remember seeing advertised were in 2002 and 2003. There was someone in Victoria who bred them every year for quite a while... coincidentally he lived right near a big population of them... *cough*
They're certainly not the easiest snake to look after, they're the most heat-sensitive Australian snake, and they're not easy to convince to eat mice. The same problems people have with Copperheads (Australia's second most heat-sensitive snake) are common in White-lippeds, but worse.