Early Fairphones were not necessarily designed for repairability. That is a principle that has emerged significantly in the last few iterations. The FP4 was the first that was really designed and marketed as fully modular from what I remember, and parts are still available.
For the American piece, the FP6 was the first available from OEM in the US.
The FP 3 was marketed as "you can replace the camera for a better one"
I still have various spare parts of my fp2: screen, camera, battery. This was in 2015 and it was modular and repairable. For the fp1, it was possible to replace the battery.