They are not available anymore, but you may be able to buy one on B/S/T here. I have one and the machined knurling is beautiful, and the output is plenty for my uses, about the same as my Gerber Infinity Ultra. Some have modified theirs with newer LEDs or Luxeons, but I have not felt the need to do that either.
By the way, I have looked at Peak's offerings but they appear to have a different "feel" from the Arc... and don't appeal to me as much.