If you don’t have a 3D printer check out the Dora Goodman Photography shop. AND if you do have a 3D printer you can print your own pinhole camera, medium format camera and so much more via the GoodLab:
The GoodLab is a collaborative space for like-minded camera builders to join together and share their knowledge and experiences. For those with access to a 3D printer, or who possess the skill set needed to build a camera from the ground up, all of our files are free to download through our open source platform. We also highly encourage our GoodLab members to customize and modify them as they wish, contributing their own ideas and creations for everyone to enjoy.
Source: https://blog.adafruit.com/2022/01/15/goodlab-provides-3d-files-and-3dprinted-cameras/
