0-50 USD depending on condition.
RG model RG31 Caliber 32 long manufactured by RG industries, Miami Florida
The serial number for an RG Industries Model RG 31 revolver is located on the frame at the bottom of the grip. To find it, remove the grip and look at the bottom of the exposed frame.
RG stands for Royal Guard which was used on all SAA vehicles that originated in Colonial South Africa during the bush wars. The RG series of todays MRAPs got their start in this era built by Armored Technologies of South Africa. There was some rumors with American Troops in Iraq that the RG stood for someone's initials, parts of the vehicle and even Roentgenium - the atomic symbol Rg etc.