When i was in parts supply there were varoius places that did this sort of thing.
Wire rope industries comes to mind.
3/16” cable and ferrules can be purchased at any farm supply, may need thimbles too. Spade bolt is another story.
I have done crimps in the vise.
Linesman knots are easy also. Will have to search the webs and find something that suits your need.
I put a loop in some synthetic winch rope. It was really easy, and suprisingly strong.