Thanks. The Pre-War S&W prices vary wildly. The large frame (N Frames) whatever their calibers tend to demand a higher price. Also the old original Ladysmiths have some pretty high prices on them. The Target Military & Police versions will be more expensive then the plain old duty or fixed sight M&P's.
Now if you should come across the S&W .357 Registered Magnum and it's in good shape and the seller is only asking $500-600 snap that puppy up. The Registered Magnums are mostly priced above $1,000 dollars anymore. They are rare and in great demand.
If you're really curious go to the Smith & Wesson collectors forum. I'm a regular there. I go by Checkman there as well. You'll learn alot about the crazy world of Smith & Wesson revolvers. The company has been in business since the 1850's and they literally have made millions of handguns. The field is huge.
I love it.
http://smith-wessonforum.com/main/