you mean the first klicky we bought as children or our oldest today?
A very good question!
I'm sure I have some original 1974 knights and Cowboys tucked away, but not ones I have owned all those years. I do like your knight, WoT, the simplicity of the figure and accessories puts the priority on imagination and making up stories, not on organising the knights into different groups and armies!
I have some US Cavalry and Artillery figures which are quite old, and several old specials, Especially the Detective and the Heevy Metal guitarist.