While the Migrant fleet did have a very small amount of interaction with the Geth at this time, (via the Migrant Marine elite and scout ships going beyond the veil), Geth technology is almost universally rigged to self-destruct or self-sabotage to prevent capture. Its still rare even after the Heretic Geth entried into the galaxy at large in ME1.

So unfortunately no Geth Armouries tech, even for Quarian elite...

Also, in order to be Vas, he must've completed his pilgrimage, otherwise he'd have the name of his birth ship with the descriptor Nar.
As well, Banishment is restricted for only the [i]worst[/i] offenses that threaten the security of the entire fleet. While attacking other quarians is pretty bad, it wont get you banished. Banishing is more of comandeering a ship and using that to attack other ships...