Here's the pistol parts lists for S&W.
Look up your pistol (you haven't said what it is) and see if the part is available.
http://www.smith-wesson.com/wcsstore...ist_Retail.pdf

Another source for parts and schematics is Brownells:
Schematics Home - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools - BROWNELLS

__________________
Science plus Art