Walther P1 questions

[Kohaku2416]

Just got a Walther p1 from my friend. Have a couple questions, and yes so far i like the gun But my questions are, what is the difference of the p1 to the p38? is the p1 just the designation for the army like the beretta is to the m9? and is the only real difference to the p1 being made of aluminum to the p38's steel? or is there any other major differences? im just currious. Also the grips on my p1 are checkered post war grips, which i dont like much because the checkering aggrivates my hands. So i was wondering can war time bakelite p38 grips either brown or black fit onto the p1? since it is mostly the same gun just different metal? also where can i find these kinds of grips at? preferred in brown. but would take black if i could find them.