Unfortunately, we need more information to give you a real answer. The value of ANY firearm is based on the exact make, model and condition. There are at least a couple of dozen models of S&W revolvers that could be described as a "38 snub nosed" revolver. Perhaps the most common would be the Model 36 Chief's Special. In blued steel, good condition, about $350.
Need to know the caliber in order to answer.
Made @ 1964.
Requires hands on appraisal
K
You can get a letter from S&W for 50 USD
It could be one of many. Impossible to answer without knowing caliber.
You will need to check egunparts.com
$100-$450.
Your Description and serial number indicate that you have a Smith and Wesson model 30,or 31 which was made between 1961-1970.
Cannot be determined from just the serial number. Need a DETAILED description of ALL markings.
200 or so
Without more of a description; 10-500 USD