I know many people only like original anything, but for many of us this isn't as important or an option. I made custom cases and discs for my SEGA CD collection. I used easily available 7mm thinpack DVD cases. They are very durable and inexpensive.
I used lightscribe for the CDs and adjusted available artwork for the inserts to fit the 7mm size. I have all of the files and will gladly share with anyone who would like them.
The entire SEGA CD library fits on 6 shelves of a small bookcase.