I am afraid I can't help with your request, other than to say I have an article on Austin from a book 'Old Families of Buncombe County, Vol II', but think this may be the same line I am trying to put together.
I am looking for info on Maggie SPAIN, whom the 1900 census of Buncombe, Co NC (Limestone Township) lists as married to James B. ALLISON (marriage of a James B Ellison and Maggie Spain recorded in Buncombe County 12/30/1885). Her mother, Ra(i)chel Spain, was also listed in the house. Her tombstone lists DOB as 1866, the 1900 census says May 1867 in NC; the marriage record says she was 20 in 1885 (=1865).
According to family tradition, she had a brother named Pinckney. If this is correct, she may be the granddaughter of Austin C. SPAIN, as the 1880 census of Buncombe Co lists Austin living with (among others) a daughter Rachel and grandchildren Pink and Maggie.