This is a base holder remix from TeachingTech Flexible Webcam Mount. https://www.thingiverse.com/thing:3223979
I wanted it to fit out of the way and not hanging down from the upper rail so I attached it to the front of the LCD unit on my Ender 3 Pro.
Unscrew the LCD, attach the base holder with the existing screws and slide in the camera base. The remainder of the items are from the original files.
I use a Microsoft Lifecam 3000 and used the tripod holder from here, https://www.thingiverse.com/thing:2235879
3D Warhorse PLA