There appears to be another standing stone at Gruline, at NM543397, in amongst some trees. According to the Canmore record it’s slightly taller at 2.45m, and tapers in at the top.
It’s not ‘strictly’ to do with the stones (or is it?), but the legend of the Cailleach is connected with the neighbouring loch (she is largely associated with the imposing mountain Schiehallion), as you can see from this excerpt from “A MacLean Souvenir” by J. P. Maclean (1913) – a fiercely copyrighted annotated version of which may be found at
gillean.com/jpmclean/
No district of Scotland was more noted for its witches than Mull. On the shore of Loch Ba lived the famous “Calleach Bheurr” and there closed her career of thousands of years. At intervals of a hundred years, so the legend relates, she immersed herself in the waters of the Loch, which ordeal gave here a further lease on life. But having waited too long for this ordeal, for the cycle had been spun to its limit, and while in the act of seeking this elixir of life, she staggered, reeled and dropped to rise no more.