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.
The author marked this model as their own original creation. Imported from Thingiverse.