Hello Brian, and welcome to the forum.
Congratulations on your first Luger. You have a great "shooter" class Luger, and should not be afraid to take it out to the range and enjoy it.
In addition to being refinished, it's had a replacement side plate installed (one from Erfurt). Even though it's got a matching number, it wasn't on the pistol when it left the factory.
To be considered collectible, it has to be close to the state it left the factory in. All matching and in original finish. As a shooter grade Luger, it's got a value of about $800 if it properly fires and cycles.
The good news is that breaking it won't destroy it's value further than the cost of replacing parts.
We publish a comprehensive FAQ document, and I suggest you download a copy:
http://forum.lugerforum.com/showthread.php?t=13121
Be warned that Lugers can be very addictive. Welcome to the obsession.
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.