I've uploaded 52 of my favourite prerolls for you to enjoy!

Check out the Plex support article to learn how you can add them into your movie watching experience!

Edit: Dalek.zone (a PeerTube instance) doesn't have a means to download the videos directly, so instead you can use YouTube Downloader and paste the list of links in quafeinum's comment below.

Edit 2: This is another option for downloading. Thank you EnigmaNL@feddit.nl