Cn. Cornelius Cethegus. AR Denarius. 115-114 BC.

Helmeted head of Roma right, wearing Phrygian helmet, its point 
terminating in an eagle's head right. EX S C behind head, 
barred X beneath chin
Helmeted shepherd Atys riding a goat right, holding branch 
over shoulder. CETEGVS below and ROMA in ex.

Cornelia 18, Cr 288/1, Syd 553, Sear 165

Extremely rare - this image from an online catalog.