Sorry- Hi Standard Sentinel began production in 1955, and I can find no High Standard with a brass frame. There were some with gold colored aluminum frames- values about $200-$300.
50-125 or so
Your Hi Standard snub nose revolver is valued at between 40-190 dollars depending on overall condition and a good bore.
80's
10-500 USD or so
Does not exist. The R 101 series was made in the 1970-80's
Try gun shops, gun shows, want ads, e-gunparts.com
James Spacek book on Hi-Standard
See related link below for DOM. As to value, no way to answer witout a detailed description of finish, condition, box, papers, barrel length, accessories, etc..
100-500; 60-70's; you will have to call S&W to narrow it down more 100 or so
50-125 USD
Try e-gunparts.com for parts. James Spacek wrote a book about Hi-Standard Pistols and Revolvers. TRY THE BLACK MARKET