Found on the FreeREG website:
County   Northamptonshire
Place   Higham Ferrers
Church   St Mary the Virgin
RegisterNumber   
MarriageDate   20 Oct 1789
GroomForename   Jonathan
GroomSurname   PARKER
GroomAge   
GroomParish   Higham Ferrers
GroomCondition   Widower
GroomOccupation   labourer
GroomAbode   
BrideForename   Susanna
BrideSurname   MANING
BrideAge   
BrideParish   Higham Ferrers
BrideCondition   Widow
BrideOccupation   
BrideAbode   
GroomFatherForename   
GroomFatherSurname   
GroomFatherOccupation   
BrideFatherForename   
BrideFatherSurname   
BrideFatherOccupation   
WitnessOneForename   
WitnessOneSurname   
WitnessTwoForename   
WitnessTwoSurname   
Notes   by banns
FileNumber   30258
However, there's also this one on the Northamptonshire Marriage Index (1700-1837):
22 DEC 1795 - Jonathan PARKER and Susanna COX (both otp) at Burton Latimer CofE
(The above are the only two Jonathan PARKER/Susanna(h) marriages on the index.)
Unfortunately, FreeREG doesn't have the relevant transcriptions for Raunds baptisms, but it may be worth having a general look-around to see if their children can be found anywhere.
Pennie