Does the Swiss Luger have a normal or wide trigger? If it has a wide trigger, then the value could be around $6,000 as a result of the limited production of Swiss Wide Trigger Lugers.
In regards to the proof marks, it sound like they are the BUG type proof marks, however, please supply more information. If the Luger has any small crosses, such as on the barrel or rear toggle link, it could mean that the barrel has been Swiss Arsenal replaced and the rear sight could have been altered.
According to your description, it sounds like the Luger is in very good condition and I doubt it is a rework.
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