Just wanted to get some opinions on what this particular model is worth. Despite my poor attempt to get some quality photos please note that the glass is not cracked or broken. Also worth mentioning is that the dial spins freely with a turn of the crank. It does appear after looking over the back of it that the top right screw is missing the nylon washer which the other three screws have. This has only been in my family for the last 15 years during which the case has never been opened so I don't know what going on inside the unit. Just curious what you guys would value this at. Thanks in advance for any input and have a great evening.

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