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If those focal ratios are correct - and quite likely are judging by the curvature visible on the photos - these things are CONDENSER lenses from projectors.
They certainly are not suitable for imaging, nor as finders, and nowhere near good enough optically for use in telescopes. Secondly, it appears they were part of a more complex optical assembly so on their own as-is, they are highly unlikely to be corrected to give a sharp or flat image without the rest of the optical train.
There's an fair bit of mis-information on surplus websites including that one, most of it intended to con the unwary into buying something that is basically useless.
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