Might the Bishop's Transcripts for Tanfield help you?
https://beta.familysearch.org/s/image/show#uri=http%3A//pilot.familysearch.org/records/trk%3A/fsrs/idgs%3A004047845.004047845_00021&hash=Mrd8SMocDIIen2Q83tu%252B82PRagg%253DIf your folk stayed in the Tanfield area it may be worth going forward and seeing if you can find their children's baptisms as well as ancestors
At times the parish registers were quite detailed - it depends on which vicar wrote them up (the Shute Barrington years 1797-1812 are very good)
If you are lucky you may find the the parent's birthplaces and / or their descent in what normally is a simple christening record.
A friend of mine has just been typing up some Northumberland records for FreeReg and the parish of Rothbury showed the mother of a child being baptised as 'daughter of (her father's name)' and 'native of (her birthplace)'. The birthplace of the parents was often included at that time
Such "extra" info won't be included in the IGI, though it will be included in the Free Reg database, if the relevant records have been transcribed.
If you find baptisms the images may be on the LDS pilot or beta sites, within the Bishops Transcripts for Durham/ Northumberland.
Good hunting!
esdel
