Hi Simon
Here are my hinges – my car is a 1950 French built 11BL
You can see that on my car they are a dome headed pin and the ends are just hammered over like a rivet. They are 60mm long and 7mm in diameter and as such they are identical to the door hinge pins.
Chris has these available from our vast selection of club spares
If yours have had bolts put in I would suggest that you go for the oversize pins.
Cheers
Paul