You can make a DIY pinhole camera from the Leica M3 tin that can be purchased from the Leica Rumors Online Store (available also on eBay and Etsy):
The 3D prints are available at Tinkercad: mask, cap, and base:
All credits go to Dan @ZDP189:
Loaded and ready for action. pic.twitter.com/6tSGgRSHEX
— Dan K (@ZDP189) April 21, 2022
Detail photos of the Candy Can Pinhole Camera: fully assembled; with the lens cap off; the magnetic base with 2 tripod mount positions; inside showing film holder (forgive the CA glue not yet painted over). pic.twitter.com/Th0TLx9scO
— Dan K (@ZDP189) April 22, 2022