Making your own cases can be fun and cheap once you know what to get and how it all fits together. I like acrylic , it is cheap, comes in colors and easy to work with. Cut the sizes you need and glue the corners together, dries in minutes.
For the really adventurous you can also bend acrylic easily at home, I use a hot air station to do it but any hot air source could work. Place sheet on table, edge of table where you want the bend in the plastic. Heat slowly and put slight pressure on the overhanging part of the plastic till you get the bend you want, take just a minute and makes pro quality rounded corners.
You can also use plastic from storage containers by cutting into sheets and bending to fit. I can get large plastic containers for about $1 each which allows me to cut sheets from it that would be about $4 each if I bought just the plastic.