Have you looked at ozlithops.com, that guy seems to have a lot of what you are looking for. I've gotten Lithops from him before. Unfortunately my wife accidentally euthanased my crop with a vacuum cleaner, that I had been carefully nursing through the winder months. Haven't been able to bring my self to try again until i get a safer place to raise them.
Subject: Re: WTB; Mesembs or Pachypodium seed/plants