I think I saw this standing stone on the brow of the hill from the minor road to the north.
If it is the stone it is near the fence line.
I didn’t have time to get a closer look as I had a ferry to catch!
‘The standing stone on the SW shoulder of Gallow Tuag leans heavily towards the north. If vertical it would stand 1.6m high. It rises from a pronounced and circular mound 15m in diameter badly mutilated by quarrying’.