This song was also in the repertoire of the much-recorded Virginia singer, Horton Barker. Barker inherited a small family repertoire, but added to it considerably in order to improve his chances in the competition-based White Top Folk Festival, co-organised by the strongly Anglophile (and notoriously racist) John Powell. In line with the festival's ethos, Barker learned some songs of English origin, such as 'Hares on the Mountain' (from Cecil Sharp's Somerset collection) and the hymn 'Truth Sent From Above (from Vaughan Williams'). His 'Sweet Sally' sounds suspiciously like an English melody, though he claimed he'd got it from 'a lady in Damascus' (presumably the one in Virginia). I can't find it anywhere in the English song archives, and the text does look like others from the US, so perhaps my suspicions are unjustified. Judge for yourselves: here's a recording made in 1941 by W. Amos Abrams.

Horton Barker: Sweet Sally