I don't doubt that an ancient historian of questionable credibility may have mentioned a man who's name literally translates to "Son of the Father", but modern religious scholars pretty much universally agree that the story of Barabbas as it applies to Jesus was a creation of St. Mark.
Evidence 1) There is no documentation outside of the gospels of a tradition in Jerusalem (or elsewhere) that calls for the release of a prisoner at passover.
Evidence 2) Even if there was, there's no way Pontius Pilate would allow it in this case since the release of a man convicted of insurrection against the Roman Empire would have been a crime in and of itself.
Evidence 3) The original Hebrew texts refer to Barabbas as "Yeshua Bar Abba" (Jesus Barabbas), which leads many to believe that Jesus and Barabbas are actually the same person, as they had both been arrested by the Romans and were on trial for sedition. There never was an actual choice between them, but rather different perspectives of the same man: One a peaceful protester, the other a dangerous rebel rouser.