When I was in England I did a short walking trip to visit as many old flint-walled churches as I could fit in. This is Coombes Church, in Sussex close to the Adur between Bramber and Shoreham. It is a hard one to find as access is by a footpath through a farm and it is hidden from view. I walked quite a long way beyond it before I realized my mistake. Its date is uncertain, but it is Saxon with later additions. Although it is a very humble building, the interior is decorated with original frescoes, also of uncertain date. One estimate suggests they predate the Norman Conquest, another suggests a date in the 1130s.
www.ipernity.com/doc/319515/52555632
www.ipernity.com/doc/319515/52555634