Joe Houser or one of the many around here with far more knowledge than I will likelt chime in soon, but in the mean time this should hold you over:
Only Buck Knives Incorporated makes the world famous Buck Model 110 Folding Hunter. The current blade steel, IIRC, is 420 HC. Other steels are available through Pete's Custom Shop (a part of Buck Knives) and blades can be changed to another steel after original purchase.
From what I gather, the Folding Hunter was not thought to be such a great selling item when it was first introduced. It exceeded any expectations and was far more popular than ever thought. It has been the working man/s knife, the bikers knife, the hunter's knife, the THE American folder long before pocket clips and one-handed opening came into vogue. 110's have been carried by princes and paupers alike and it's still one of my favorites.
If all of the foregoing were not enought to make you a fan, Buck Knives and the people who runt he company have one of the very best reputations in the industry for customer service, business ethics and appreciation for their customer base. Moreover, they are salt-of-the-earth people who I will feel privileged to spend eternity with. If Buck made widgets, I probably go out and buy one, but it happens that they make really, really cool knives - most favored among them being the model 110 Folding Hunter!