6x7 / 67 bodies are pretty complex in terms of engineering and repair costs could very easily exceed the monetary value of one or even two replacement bodies of equivalent or older or newer vintage, of which there surely must be millions around. The dial is linked to resistors and copper mesh and replacement usually requires fixing a lot more than what has failed, e.g.corroded circuitry or parts that have just worn out through old age. It's a great camera with a long heritage but it is not immune to the ravages of time and rough treatment.
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