VM is correct and I've seen them go for quite a bit more than his estimate ( before the economy tanked) . N frame grip adaptors are the most common, with the K frames next and I've only seen a couple J frame adaptors in 60 yrs. N frame replicas are available but no K or J frame replicas have been made, to my knowledge. There's a little bit of S&W trivia related to these adaptors. Some years ago when Roy Jinks came across the record book for the Registered Magnums in the archives, we noticed the letters "GA" typed on many of the order sheets, but not all. It took awhile before we made the connection that the "GA" indicated that particular gun was shipped with the grip adaptor installed. Ed.