"Job (1675-1754) had a grandson, Parker (1752-1837), of Boxford, Mass., whose first wife was Hannah Flint. She died 13 October 1802, but I cannot find a record of their marriage (date or place) or Hannah's birth date/place."
Brigham's Tyler gen. says they marrried Jan 29 1782, but does not say where (p. 140).Parker's Rev. War pension file has his testimony that he lived first in Boxford, then Sterling (Worcester County) MA and then Leominster where Hannah died.Neither the Boxford nor the Leominster VR has the marriage or children's births.If you haven't tried Sterling, the Family History Library has films of the town clerk's records--perhaps the record is there.
Brigham says Sally Gray was of Wilton, NH and a history of Wilton by Abiel Livermore says she was b. July 11, 1791 daughter of Joseph Gray and Chloe Abbot (p. 384)I didn't check the FHL for records for Wilton.
Joseph Augustus might be the Joseph A. who died in Leominster, MA in 1902. 1900 census has Joseph and Dolly in Leominster (Series: T623Roll: 692Page: 222) Joseph 70, b.NH.The NEHGS online index to the MA VR to 1910 has this Joseph A. indexed, but the death record is not yet online--you might want to try to get the record from the town clerk and perhaps check the database also for the wife.
I'm sorry to be so sketchy, I know nothing of this line and I had time only for some quick lookups and am rushed.Good luck, I hope some of this may have been helpful.