No coins have previously been recorded for the Julio-Claudian period for Gargara, the earliest imperial issue otherwise being for Vespasian (RPC II, 901). The head is presumably Augustus. Coins of Augustus are mentioned by Head and BMC (p. xxxviii), but not actually attested before this. As for the countermark, A Latin letter would be a bit unexpected, so perhaps B is a possibility. KM 39, 7 mentions a K on its side ‘im Felde eingeritzt’ for a coin of Vespasian, omitted in error for RPC II, 901/2, but visible on the illustration at the top of the reverse.