Why not coindicence range finder? A watch maker and optician can make the lenses and small gears.
Or the donkey ears style trench binoculars/rangefinders.
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No batteries required.
Note, that in the case of T2K several Warsaw Pact countries were fielding these still as regular equipment in active units at the start of the conflict.
It is NATO that went the more high tech (and efficient) route that is suffering with the collapse of economy and industry.