Where to buy Bluelectric cartridges

I have been searching for information on where to buy Bluelectric cartridges (such as MicroMagic Altair, Silver Spirit and Magic Doamond) in Switzerland and the USA. I have found a couple of dealers in the US but the info on dealership in Switzerland was very much out-dated. I have found this link: "www.dietiker-humbel.ch/micromag.htm" , but the web page was not available, so I sent an email asking if they are still carrying those cartridges, but never received a reply. I would appreciate any info on where to find one of those cartridges in Switzerland.