Ok, I know UGCs are coming back into stock soon, but I may have an alternative for us yanks, if not temporarily.
http://www.usplastic.com/catalog/item.aspx?itemid=44689&catid=886Basically they are 28mm DVD cases, whats nice about them is, I was able to get a NES cart to fit in to one without modifying the case, just take out the disc pages. Also it has the clips that can be used to hold manuals.
something to look into. They do not sell in bulk, so you can buy as many as you need and not have any left over, and I have some of their cases, they are not bad quality.