For a production slip joint, Great Eastern Cutlery makes a nice knife.
Yes they do and would be my first choice. Probably followed by something from Buck as a second choice.
And that would also be my suggestion. I toured their factory and have several of their knives although I've lost or given away more.
GECs are the nicest factory made slip joints I've ever saw. I have a handful and they are all excellent.
The big issue with them at this point is beating the collectors to them when they come out. They only do a few runs of a couple different patterns a year. You might wait a couple years for a stockman to be made then you have to get on a early reserve list to get one. Or pay about double the price on the 2nd hand market.