A DIY Inexpensive Optical Viewfinder for Compact Digital cameras with a hot shoe. - YouTube
A rather battered but classic 1930's German LEICA analogue 35mm film camera with an Elmar ƒ4 , 9cm (90mm) telephoto lens and an extra hot-shoe mounted viewfinder Stock Photo - Alamy
Amazon.com : Ricoh GV-1 Viewfinder : Camera And Camcorder Viewfinders : Electronics
Attachable viewfinders - not only for Leica cameras
Sigma VF-11 Optical Viewfinder on the Fujifilm X-E1 – Lonely Speck
A rather battered but classic 1930's German LEICA analogue 35mm film camera with an Elmar ƒ4 , 9cm (90mm) telephoto lens and an extra hot-shoe mounted viewfinder Stock Photo - Alamy
Ricoh GV-1 External Viewfinder | Digital SLR Camera, Digital Cameras, Toronto Canada Digital Camera Store, Aden Camera
Sigma VF-51 External Viewfinder AV6900 B&H Photo Video
Hot Shoe EVF For Canon G1x
Amazon.com : Xuan 35mm 28mm Optical Viewfinder (28mm) Black : Electronics
HOT SHOE VIEWFINDER #3DThursday #3DPrinting « Adafruit Industries – Makers, hackers, artists, designers and engineers!