You can order them directly from noisecontrol.de in germany:
Silverado
I have one...been using is for a couple of months now. To be perfectly honest, I have mixed feelings about it. Don't thinks its as good as it was cracked up to be. Its fairly quiet and is easy to install. I occasionally get a slight case vibration caused by the two fans not spinning quite synchronously. The cooling is mediocre, in my opinion. About 32C idle and up to 58C full load after 30 minutes of Q3. This is with a 1.33 tbird oc'd to 1.5 using VIA hardware monitor(not the best for accuracy from what I have read).If I had it to do over again and was considering that much money (which I won't ever do again, buy the way!) I would probably been better off with the Swiftech 462 for about the same price or Zalman 5000+, which can be had for about $45. If your really interested and don't want to order overseas, I will sell you mine

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