Just a suggestion:
If you want a "collector-type" P38 then expect to pay more, but you will wind up with a genuine WW2 classic that looks great in a glass case..
If you want a "shooter", then I recommend the later P1.. In fact the later P1 with the "fat slide conversion" which (I understand, could be wrong) includes better white dot sights, a heavier slide and a hex bolt in the frame. These P1's are, for practical shooting, IMO preferable over a "real" WW2 P38.
I'm a big Walther fan, and I'm well pleased with my P1. My P1 came "as new", and it a pleasure to shoot and quite accurate.
Another suggestion.. Check out the surplus P5's on the market. (SOG?). I bought one of those and the P5 is like the "final" improved P38's... (Or so I read). The P5 has a reputation for being a surperb firearm with exceptional accuracy. It'll cost you another hundred bucks or so, but would serve well as a personal defense gun should you desire it.
Any of these older Walthers are imo excellent, high quality firearms. You might check out the forums at:
www.Waltherforums.com,
www.Handgunforum.net (Walther sub-section), or
www.Glocktalk.com (sub-section Gun-related club forums).
You won't regret buying a P38, P1, or P5...
Best Wishes,
J. Pomeroy