Near identical examples are published in Torsten Edgren, pg 475, found in grave no. 16, Tuukkala cemetery in Mikkeli, Savo, E Finland.
The piece shown above is now published as Fig. 1.1.2-d on page 36 of Hammond (2013), British Artefacts, Volume 3 - Late Saxon, Late Viking & Norman. He attributes it to the Mammen art style.