Free
I upgraded from a Raspberry Pi 3 to a 4 and could not find an existing case that I liked, so I modified the Pi 3 case from giacomo30196 ( https://www.thingiverse.com/thing:3016364 ) that I had been using for years. This was designed to hold the CanaKit fan that comes with their Raspberry Pi 4 bundles. No supports are needed. You could use screws to hold the halves together, but I find friction fit is enough.
Updated 7-27-22 Several variations of camera ribbon, display ribbon and gpio pin ports have been added for the top part.
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