So I just finished scrolling this thread again. Maybe for the 10th time or so. And I only found one knife here that has the brass back, seen in post 51. That was one of the great features of early Randalls was that feature until the welder who was doing the work up and died. I've even had jobs where I thought I'd have to die to stop doing something or the other.
Just for reference, the brass back was soft brass so in knife fighting, the other guys knife would stick or catch in the brass and not slide down the knife to the hilt. That would allow guy with the brass to control the opponents knife and with luck, wretch it from him. So if you're a buyer and see a brass back, buy it quick. Its rare and proper. After all, a proper knife is a huge advantage!