Well, with my limited knowledge, I will get you started. The two Eagle over N are proof-marks, used for both military and non-military Walther's. I believe I read 335226P as the serial number which would place it in 1941, which is also the first use of the Waffenarnt ( Army acceptance code ) E/WaA359 which seems to be stamped on the left side. So, I would think you have a Walther pp German army acceptance markings ( a gin-u-wine war trophy ) Value is hard to say, the picture of the holster did not come through, but if it is correct then that is a plus. All WWII items are gaining in demand, and PPs and PPKs seem to be one of the most desired items. Now this is just a guess, a WAG on my part, your gun is well worn but even so no major problems, The gun and holster should bring 8 hundred to a thousand ( maybe more ) to a collector. Hey guys, If I'm low or high on the value, please jump in. Don't know if your married or have kids, but IMO that would be one hell of a heirloom from one of the Greatest Generation, your grandfather. Best I can do, hope that helps.