I've done some checks.
I've found 4 variations of this set of armour, so far: Powertech (metallic), Medic (orange) , Vanguard (grey) and Commando (white). The vanguard/commando parts can be obtained from:
Belt (not upgradeable) = [Heroic] Shifting Priorities
Legs = [Heroic] Justice for the Lost (Bonus Series 1, I believe)
Helmet = [Heroic] Mandalorian Terror
Gloves = [Heroic] Industrial Sabotage
Boots = [Non-Heroic] The Neutraliser (Bonus Series 2 - not repeatable)
The chestpiece for Commando can be crafted, Medic drops in Taral V. Haven't found the chest for Vanguard yet and have only seen Powertech on the GTN.