Walther PPK Pre WWII

I have a Walther PPK Pistol that my dad got in Germany during WWII. It has the Brown Plastic Handle and it has a crown over an n,
the serial number is 183583 K. I had someone tell me it was pre WWII and then another said the K after the serial number meant it was made in the 30's. I have the old holster that is rather worn but the gun looks good. Could anyone give me an idea of what it might be worth. I am thinking of selling due to health reasons and I dont wont to get taken advantage of. I have seen so many values all over the place. Should I take it to a reputable auction house. Thanks for all ur help.

ppk's are kinda tough to give actual values mostly because on condition and history behind it..if you can document it to a specific person even commercial models can bring good money,,judging by your description a run of the mill average condition pre ww2 ppk should bring between 400-800..if it has a ww2 marked holster it may add to the value even if the holster is worn..
bigcurt