Hi Robin
www.familysearch.org has a member-submitted entry (so needs to be checked against parish records) for the marriage of Jacob HUNN to Tamasine HOLMESE 3 Nov 1835 Acle, Norfolk
also a marriage for possibly his parents (also member-submitted)
Jacob Hunn to Amy Jermy 6 Apr 1801 Acle, Norfolk
There are two baptisms from extracted parish records for
Jacob HUNN Birth: 9 Mar 1810 Christening: 11 Mar 1810 Acle, Norfolk,
Parents: Jacob HUNN and Amy GERMANY
and James HUNN Christening: 22 Nov 1813 Acle, Norfolk, England
Parents: Jacob HUNN and Amy
If you got the birth cert for the youngest child Joseph shown aged 2 on 1841 census that should give you his mother's maiden name, and a later census should show birthplaces and more accurate ages for the couple, as ages were usually rounded to the nearest 5 years.
Barbara