I have found that Rocca brothers (Marlows) stock 2 types, one has a smaller rivet on the gold coloured lever, the other is thicker and hence stronger. Check this when buying. Another reason the handles break is the door itself. The design of the hinges allows the door over time to drop by a few millimeters. The rear of the front door should be level with the front of the back door (use a ruler). When you open the door, you have to lift it as well, exerting extra force on the handle, eventually breaking it. To adjust the door, you have to remove the front quater panel and get someone to lift the door as you adjust it. The door, if done correctly, will open like a dream.
This may save you the trouble of modifing the door for camira handles.
XF died, Now It's a 6-cyl Cortina!
Rear ended 3 times, 4 close calls.
All while I was stationary, still counting the idiots..