Jaguar indie i guess bud.
They are rare so Merc or BMW indie could also be competent but might not have the diagnostic gear.
You could try making a Lazlo ABS Sensor tester, see the thread in our Stickies. That will test the ABS sensors dynamically.
Or if you can get and use an oscilloscope that's way better.
Or to rule them out the rear ones are only £24 each.