Legion near Judea at time of Jesus

[Nathan Ross]

what would have been required to suppress the alleged rebellion of Barabbas.

Whether it was a rebellion, a riot or an insurrection, I'm sure the normal auxiliary garrison of Jerusalem and Judea would have been fully capable of dealing with it. That was their job, after all! There would be no need for Pilate to summon help from the legions, even if he had the authority to do so.

So what would the soldiers have looked like?

There's an illustration in Graham Sumner's first Roman Military Clothing book of an auxiliary soldier and centurion in Judea cAD30, the soldier in 'plain clothes' riot-control outfit. Neither wears armour - unless a battle was expected, this would probably be their likely everyday appearance, I think.

There's a common assumption that all Roman auxiliaries were dressed and equipped in the same way across the centuries - a bit like this perhaps. But troops in the east, in the early decades AD, quite possibly looked a lot more like their Herodian precursors. Locally-made equipment may have been common, and perhaps only the unit standards identified them as Roman. There are very few armour finds from the period, I believe - and lorica segmentata is almost unknown in the east at this date (the soldier in segmentata at Gamla was from Legio V Macedonica, and came from the Danube).