Lamp cap is a prop for an old English style street lamp. A box can be made out of wood to enclose a lamp socket. Use Thing: 3211293 as a post adapter https://www.thingiverse.com/thing:3211293
The bottom is in a pyramid form to save material. There is no need for support.
lamp cap.stl has a 140 mm square base, a height of 160 mm, a lip of 15 mm and a lip thickness of 2 mm. The screw holes are suitable for #8 wood screws.
Used glue on the print bed to make sure it did not move. It is a 12 hr print.