I am not sure if this is funny or sad, or both; but this is a listing on Vcoins that seems a little pricey at $4,000, but at least it is marked down from $5,000
For me, this is simply an unofficial coin (note the odd appearance like the eyes and the completely improbable ends of the tie of the diadem), but below is the description-
Unpublished & Unique Constantinople City Commemorative "Constantine Bust & Soldiers" Lyons Extremely Rare
"Constantinople City Commemorative. Lyons Mint Circa 330-337 AD. Obverse: CONSTANTINOPOLIS Laureate, draped and cuirassed bust left of one of the sons of Constantine I The Great. Reverse: GLORIA EXERCITVS Two Roman soldiers holding shields and spears, flanking two standards: PLG in exergue. RIC: -, Unpublished, Unique (Early Prototype?). Size: 16mm, 2.03g. Professional Numismatic Notes: Around 330AD the mints of the Roman Empire began minting a series of coinage commemorating the founding of Constantinople, and also a series commemorating the existing capital of Rome. On these coins, typically you see a personification of Constantinople named Constantinopolis, and the reverse usually of a victory or soldiers and standards. This coin is a unique and heretofore unknown type in this series, featuring a Constantinian bust instead of the city deity. The legends are clearly that of a Constantinople commemorative. My hypothesis is that this coin may represent the earliest attempt at minting the commemorative series, but instead of utilizing a new obverse type they merely changed the legends of an existing type. This coin grades in good VF with a pleasing untouched and natural green and yellow patina. There is some patina flaws on the obverse, and a large surface scratch on the reverse. This may be the only chance you'll ever get to own this coin or a coin of this type in general!"