This is an Iron Age Bury A Unit. The die study conducted by Dr John Talbot identifies this coin as part of Die-group 2, Obverse C, Reverse 3a. This 3D laser scan was conducted by Central Scanning on a ZEISS COMET L3D 8M.
Reference: Talbot, J. 2017. Made for Trade: A New View of Icenian Coinage. Oxford: Oxbow