Well - this is a speculation - and I don't think you're going to get away without buying a certificate, but
There is a death in Bath Q3 1839 for a Charles Windsor (Vol. 11 Pg. 39)
There is also a marriage fo Charles Windsor on 15 June 1834 in Chalcombe, Bath, to Sarah Ann Neads.
Just a thought - may be worth persuing - I can't find a bap. for Mary Elizabeth.