My SAK has the Victoria (w/ crossbow) tang stamp on the main blade which suggests this SAK may have been produced between 1960-1970. The condition of the scales is still good even after almost 50 years.
I did some research on the company etched on the scale "RHG Electronics Laboratory, Inc". It was a company founded by Arnold Rubin "R", Ron Hirsch "H", and Robert E. Gruber was the "G" in RGH. They manufactured log amps and mixers along with associated products used in the microwave and RF industries. They started in Farmingdale New York in 1960, relocated to Deer Park New York some time after 1970 when they needed larger facilities. They were subsequently sold to other companies including M/A-Com. Their products are still available for sale today.
Victorinox Tang Stamps
http://www.microwaves101.com/encyclopedia/wherenow.cfm accessed 17 July 2014.