Weirdly marked as stone instead of B.S. as they are on the boundary to the North. Maybe a few of the chambers stones were used as boundary markers. It looks quite clean and fresh, more so perhaps than other standing stones thereabouts.
There may be a growing trend to construct 'ancient' monuments as someone has built this in the Biddulph area too. https://www.flickr.com/photos/16543087@N03/8434764065/in/set-72157631375423652#