Yes, they are one and the same.

>on the maps its sited by Boulters Barn.

Sorry, I disagree. Boulter's Barn is over 300metres to the east, far past the Three Ways road junction. East Churchill Grounds farm to the north, whose hedge the stone lies within, is much nearer.

http://www.magic.gov.uk/website/magic/viewer.htm?startTopic=magicall&chosenLayers=moncIndex&xygridref=429284,225655&startScale=5000

http://www.pastscape.org/hob.asp?hob_no=332495&source=textonly&period1=None&county1=Oxfordshire&class1=None&hob_name1=Standing%20Stone&min_date1=ALL&max_date1=ALL&type1=&place1=churchill&page=first&recs_per_page=60&s_o=1&nmr=&defra=