You've got most of the available information already, what more do you need? In the late 1950's there were a slew of Western shows on TV, at one time more than 30 different shows were on during the same time period. About the same time Colt make the very wise ( ha ha ) marketing decision to stop making the Colt single action. To meet the great increase demand for " cowboy guns " a number of importers jumped into the fire with their products ( and at least one home grown, Great Western ). Herter's conspired with Saur and came up up with the .357/44 Mag. to also complete with Ruger, they were able to do so for a short while because the German Mark was then undervalued which made their products cheaper to buy in the US. The revaluation of the Mark and the 1968 gun control act put an end to the endeavor. That boys and girls, completes today's history lessons and I make no claims to it's accuracy. Heck , some of it may even be true.
Value is listed at 400 if in excellent condition down to 75 as in boat anchor.