Watch List notes:

MOESIA. Istros. Circa 280-256/5 BC. Drachm (Silver, 18 mm, 5.63 g, 12 h). Two facing male heads side by side, one upright and the other inverted – a tête-bêche pair. Rev. ΙΣΤΡΙΗ Sea eagle standing left on dolphin; below dolphin, Δ. AMNG I 420. Dima Subgroup VII. HGC 3, 1803. SNG BM Black Sea -. Nicely toned. About extremely fine.
From an old Swiss collection formed way before 1990ies.