Found George Barton Prior's marriage licence, it says Eliza was 25, so born about 1799 / 1800. before Richard Prior (George's father ) married Ann Brownbill. George died in 1835 but Eliza / Elizabeth (she uses both on censuses) outlived him by a number of years. She is consistent in age and birthplace, Born abt 1799/ 1800 at St Helens. Marriage record says she was from Prescot, which is near St Helens. There is a baptism for an Elizabeth Prior on 1st Dec 1799 in Prescot (born 23 Nov 1799), daughter of James (occupation agent), no mother recorded. This seems a much better candidate for Eliza, given her age and birthplace.