And I think I remember them saying that the quote they got for aluminum cases on the second run was about twice as high as the first, lol.
Massdrop was selling kits for $200 (+ shipping and import taxes, if outside the US), once their minimum number of orders was met; though price could vary if you wanted extra PCBs or something, or if you didn't want switches, etc.
If you wanted to make up your own, the design files are here
(the case most everyone is using is the acrylic case by Litster). Also, if you (or anyone) really was going to go the the effort to have them custom cut, you should probably know that there was a little issue with the placement of the cutouts for the stabilizers on the 2x keys with that design. I've only heard a few people complain though, and they figured out workarounds (and everyone says that stabilizers aren't really necessary anyway...). You'll have to search the GH thread
for details if you're curious, I forget if it was mentioned here.