We have been looking everywhere including on Ford website and can't seem to find the ABS speed sensor ring that goes on the rear brake drum hub. The brake drum has 4 threaded bolt holes for wheel bolts and two dowels to locate the alloy wheel. It is 180mm internal diameter and marked as Fiat internally. it has integral bearings with an abs sensor ring on the end.

The Ford website has two ABS sensor rings but neither of these are correct as it looks like the magnetic surface is on the face and not the side. The ABS sensor is not flush with the back plate but it protruded in about 10-15mm to detect the magnet poles on the side of the ABS ring. Any ideas where we can get new ABS ring and how many poles it is likely to have, failing that new complete drum/bearings/ABS ring?