My suspicion is that this is a late Rome about the end of 4 or 5 start of the century. I speak from the manufacture of equipment and the type of the coin.
Your reverse is GLORIA ROMANORVM and the mintmark is SMKA, so it is from Cyzicus. It was issued by either Theodosius II or Honorius, but I believe that I can see DN H on the obverse, so Honorius.
@pascha Your link states a R1, so it's considered 'rare'......or the lowest rating of rare...and I've always considered those to really mean 'highly scarce'. Of course condition is always 'King' and rare does not always equate with value.
Is the "R1" rating from RIC? If so, the ratings are obsolete since the writers of RIC only took into account coins held in museums and major collections of the time. In addition, there have been many coins unearthed since the writing of RIC. I wouldn't put much stock in RIC ratings.
Bing, of course you're right, but I speak from ebey sales and auctions, and so for them this nonet still rare.
The post-408 (Arcadius died in 408) GLORIA ROMANORVM 2-Emperors reverse type shows 2 standing figures. Although they were minted over a longer period of time, they are, in my experience, just a little harder to find - in decent condition, at least - than the earlier 3 standing figures (3-Emperors) GLORIA ROMANORVM reverse which preceded it. In general, this is not a scarce type in either the 2 or 3 emperors version, but compared to, say, GLORIA EXERCITVS 2 soldiers and standard(s - 1 or 2) or fallen horseman FEL TEMP's these are not seen nearly so often, but I wouldn't call them "scarce" by any rational measure. In the case of this coin, the obverse is below average and the reverse a little above average in terms of the condition in which they tend to be found. There are some minor varieties with them holding various objects between them or not holding anything - yours seems to have a small globe they are holding - but it's not anything to consider as a rare or even scarce variety, just an incidental feature of the type.