This is a case I made in tinkercad for my Raspberry Pi 5 to replace the case that was originally designed for the Raspberry Pi 4.
There are 3 versions:

• v1 is close to the original dimensions without fan hole that I used to get a rough idea of what I wanted, it may need some work.

• v2 is slim, with fan hole. I ultimately didn't use this, so again, may need some work but should be 99% there.

• v3 accommodates the Pimoroni NVME base underneath the Pi 5. This is what I ultimately went with. I added a debug probe and power button manually after-the-print so they aren't modeled in.

You will need to ensure you have standoffs that are of the appropriate size. I didn't originally intend for this to be for public consumption, so you may need to make some adjustments. TinkerCAD link is here:
https://www.tinkercad.com/things/luMLVHCEj5E-pi-5-dsi-case?sharecode=PcF122c4JpGSafm8WAZFUIrpsNJss0fkeWomMnTJi9k