... in a style similar to those of Menander I, has the same type of Athena, and shares one of Menander's mint marks. On the coin, the title of Thraso is "Basileus Megas" ("Great King"), a title which only Eucratides the Great had dared take before him and which is seemingly misplaced on the young boy Thraso ...The Thraso coin has never been photographed. Wikipedia cites R. C. Senior, Decline of the Indo-Greeks (1998) and says "The coin belonged to a secretive coin-collector, who did not allow Senior to photograph it, and it remains unpublished."
Not only is the coin unpublished, it may represent a portrait of Thraso whose appearance is otherwise unknown. The bronze coinage of Menander is described as having Athena's head on the obverse. This description comes from James Prinsep (“New Types of Bactrian and Indo-Scythic Coins, Engraved as Pl. XXXII”, Essays on Indian antiquities vol. 1 (1858), p. 399). Prinsep named the obverse bust as “Athena” and this has stuck although the features greatly resemble those of Menander himself!
Not to scale. The coin on the left depicts “Athena”, the right Menander. That Athena sure looks a lot like the first Greek Buddhist king.
(Images used without permission, but are from cngcoins.com, the the tetradrachm is available in CNG's web store.)