Another good team result, cheers gents. I knew it may not be specifically highlighted on the old OS Maps but occasionally they do show something "off the norm". It did look like the Workhouse locality was most likely given it's central "Number One" address and other key village features/buildings nearby, but like S I wasn't absolutely certain, so thanks Maurice for confirming it.

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2017 Update, the excellent Workhouse site confirms the above location and far more.
http://www.workhouses.org.uk/WestburyOnSevern/