By coincidence I have one of these lovely watches with me at this time. It was almost running but after opening it - which took all the power of the bench opener-- it doesn't anymore?!? Waiting to know if the owner will accept my modest estimate for service.
Now for the value aspect, I don't really know first hand, but for a realistic estimate I would check chrono24 and subtract 20% from the asking price of the better comparable piece.
Really? I have not see any reports or mineral glass crystals shattering so terribly. The expected use of a dress watch should not involve such potential destructive shocks.
I would not replace a mineral glass with acrylic, but I would replace it with sapphire, because scratching is the actual, common and annoying occurrence.
4 digits Suffixes are the case number, together with the mov.t they make the basic watch reference.
You can finnd size specifications oine or measure it. Before giving up on it check pulse at the coil, if there is try a line release or demag.