Good afternoon, Richard..... Do you have a photo of the gun?
The original .44 magnum model 29 was manufactured starting in 1955 and through several variations for many years. The engraved models was done by the custom shop but also by private gunsmiths. The factory engraved revolver from the custom shop came in a mahogany and is still available today from the factory here:
http://www.smith-wesson.com/webapp/wcs/stores/servlet/Product4_750001_750051_766362_-1_757780_757751_757751_ProductDisplayErrorView_YGiven the serial of CRB this would date the gun to the mid 90's. The value would be as follows:
Type: PistolsMake: Smith & WessonModel: 29Caliber: .44 magnum 44 specialCapacity: 6Barrel Length: 4Total Length: 9 1/4
Low Price : $1050High Price : $1129
Since these are still available the gun does drop in value a small amount initially but in later years this revolver will of course become more valuable as supply drops due to damage, shooting mint revolvers, lost/stolen guns, etc. So the reasonable high end for private sales would be right at $1129 (and only a few dollars more for a "new" one from the custom shop with varying barrel lengths available).
This was also available in another design pattern in the early 90's and depending on the exact date of manufacture this pattern is a possibility: