Hi Debbie,
The IGI has a few entries for the name (variously spelled) in Oxfordshire - though the IGI seems pretty poor on Oxfordshire records.
However, confusingly (in the light of the entries you found), it has the following baptisms:
William BAGGS, bap 4 Nov 1787, parents Phineas Foxell BAGGS & Maria
Wm BAGGS, bap 14 Nov 1787, parents Phineas Foxall BAGGS & Maria
Both extracted entries, both Aston Rowant, same batch number (C038311) and same film number (0095204).
JAP