In fact “ barbarous radiates” were produced unofficially as an ‘illicit’ currency from the third century or earlier , and tend to mimic the official currency then circulating for example the radiates of Tetricus but also the non radiates of the family of Constantine and later. On many of the third/fourth century Roman sites that I have detected they are as frequently found as non barbarous coins so they clearly circulated widely.
Yes, this looks like a “barbarous’ coin to me, and a particularly interesting example.
Jerry