Just wanted to say I found a base for my S&W 29 from a company called Cheaper Than Dirt. They have an unbelieveable amount of items for sale. Cheaperthandirt.com
The item is a Weaver No. 401S Base S&W L,K,& N Frame Revolver Standard 1-Piece Detachable Top-Mount Base Silver.
Price is $6.71. The item # 63582. It says the Manufacture is Weaver 48001.
Fits S&W L,K, & N frame revolvers & 629 Classic factory drilled & tapped. Includes custom-hardened screws for mounting. Remove rear sight to use. Silver.
If you get a chance, check out their web site and you will be amazed at everything they have to offer.
Foreman1943