This is a simple slide in mount for a Salange HY320AA Projector.  Since the base doesn't have screw holes, you can print two of these and slide the edges of the base into them.  Fastening the parts to a wall/ceiling should be stable and prevent the projector from moving as the two opposing sides have an end stop to keep it from sliding back out.

Recommend printing this in at least PETG as PLA will likely warp over time under the minor strain of the weight.