this post. These guys are more of them, but with flak armour instead of carapace. I call them The Penitent.
Their story is they are wash outs or drop outs of the Schola Progenium. Those that couldn't make the cut and become real Tempestus Scions. They are now seeking a second chance. They find it under the Inquisition. While most inquisitors want the best of the best, they find a certain drive and determination from these individuals, and ideal for expendables. Many of these Penitent will do anything to redeem themselves, asking only a second chance.
warzone minis. Again, I have used this deal for a lot of my conversions in this army, and it is one hell of a deal.