[alchemy]

Can you show the other side of those lock pins? I'd like to know if they had a groove in the side of the shaft like a normal lock pin. If not, what presses against the kingpin tightly?

If there is no groove, and they are just straight shafts, I'd think a resourceful machinist could replicate something from a pair of bolts. Maybe just need to weld a knob onto the heads?