Toronto. In early 1981, at one of our fairs, I bought an odd looking viewfinder from a Mr Hyman. Actually, he had a box of Leica stuff that I picked up. Most items were for use with Telyt 20cm lens (not included).
There were a few copies of each item. The 200 mm viewfinder (SFTOO) is an enclosed black frame sports finder with a distance adjustment from 10 feet to infinity.
First made in 1938, the viewfinder survived WW2 and was marketed to around 1968. The examples I have are like new and likely post war (accessory foot and distance ring are both satin chrome).
Drop by one of our events – you may even find such a viewfinder for a Leica or other 35mm camera!