I got a Corsair 5000D airflow case from a friend for free but it is missing all the four screws that hold the side panels on the back. All the screws I can find on the internet are the short version that don't have enough reach.
This screw is from my own PC case.
Edit: image with the short version that I was talking about
The term to search for is "captive thumbscrew". The captive part being the unthreaded portion which allows the screw to rotate freely in the panel hole. These will tend to be longer than normal thumbscrews you account for the unthreaded part.