Paul
I used these from Snakebite:
Classic Door Handles (pair) [HAD02] - $48.00 : Snake Bite: Cobra Parts & Accessories for your AC Cobra 427, Cobra Kit, Ford/Shelby Cobra, Cobra Replica, Cobra Kit Car
They came in a kit with the ferrules to fit in the door, the shaft and the lever to sit inside the door that joins to the latch. I put them at the front of the door and linked them to the latch with some 3mm rod.
You can just see them in this photo. If you are interested I will take some close ups.
Geof