Watch List notes:

Bimbisara and Ajatashatru. 6th-5th centuries B.C. AR karshapana (25x19 mm, 3.37 g). Series I. Five punches, including a sun symbol (twice), 6-armed symbol, 'Mathura tree', elephant, and one uncertain punch / Sun symbols. Gupta & Hardaker 188. The Series I coins are the earliest issues of the Magadha janapada and are all very rare. Very fine. 

Gupta and Hardaker attribute all series I coins to the kings Bimbisara and Ajatashatru, which would make them contemporary to the time of the Buddha. Indeed, Bimbisara offered his kingdom to the Buddha and the Buddha attained his enlightenment while living in Magadha.