High-quality keyboards used to routinely cost 80-100. I haven't seen a "high-quality" keyboard made in ages; most modern keyboards in that range just have more useless rubber-chicklet "multimedia keys" or wireless or something and are still made with lightweight materials and membrane construction.
This particular keyboard is a low-quantity custom keyboard with blank keycaps, so I'm not suprised it costs more. And if it uses actual keyswitches rather than a membrane, there's your costs right there.
My favorite keyboards are made by NMB, but I don't think they make consumer keyboards anymore. Really old Compaq, IBM or AT&T keyboards are also highly regarded (modern Compaq keyboards aren't so hot). I'm using an NMB keyboard right now and it weighs about as much as three or four Belkin, Memorex or Logitech keyboards.
--Chris