Here is a really nice example that recently sold on eBay for just over $400
Decentius, AD 350-352.
27mm // 4,48g
Obv: MAG DECENTIVS NOB CAES, bare-headed, cuirassed bust right.
Rev: GLORIA ROMANORVM, emperor on horseback right, wielding spear at a suppliant, bare-headed enemy before the horse. Shield and bent spear beneath the horse. Star in upper right field. Mintmark RP.
RIC VIII Rome 210; Voetter 7; Sear 18868.
Exceptional and rare piece.