undetermined silver-plated coin

Celtic contemporary ancient imitation?, modern imitation?,
Didrachm(?) (19-20 mm / 5,31 g), silver-plated bronze, axes about medal alignment ↑↑ (ca. 330°), fire damage?,
Obv.: laureate head facing right, bearded.
Rev.: youth on horse trotting right, wreath or two branches before under left foreleg in lifted position, dotted border.
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