Couple of options, you can make your .204 brass from the parent case, .222 Rem Mag.

On ebay there is a guy selling once fired .204 brass by the bundle of 200. Seems to be going for around $40. His handle is obsessionone.

Then there is reloding your store bought ammo.

Cabelas is much cheaper by the way then Mid South, they want $22 for 50 and are back ordered.

Anytime a new cartridge comes out it takes time for the brass to get out. Hornady is the only manafacture making the .204ruger ammo right now, and they will be more concerned on getting the ammo out before the brass. I figure the brass should be hitting more stores soon. When it comes out, the brass will also come down as it is more available.

By the way, Rifle's Handloader has a good article on loading the .204ruger in the December 04' issue.