This one is a little rough, but officina A is a unlisted, RIC only lists officina Γ for Arcadius. This coin is also neat because it has the full spelling of AVGVSTVS on the obverse.
Arcadius
A.D. 383-388
22mm 5.1gm
DN ARCADIVS PF AVGVSTVS
VIRTVS E-XERCITI Emperor standing right, holding standard and globe, left foot on captive.
In ex. CONSA, Tau-Rho in left field
RIC IX Constantinople 83c