Raymond,
Congratulations on a very nice Commercial Luger. It's condition and rarity contribute to it's value.
If you want to insure it, you can get some idea of retail pricing by looking at some online dealers. For example:
http://www.simpsonltd.com/index.php?cPath=179_180
There are over a dozen on there as I post this.
I think you'll see what a cheat the purchase offer at the gun show would have been.
I agree with John's advice about maintaining it. Do your best to document it well and enjoy it.
To Jack (Above) the Luger has the "
v" suffix on the frame. It's not unusual to find that the suffix is not on the barrel below the serial number stamped there on Mauser Lugers.
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.