Glad you like it mate, im loving it.
The chest piece is called: Pristine Vindicator's Chestguard
I got it from Hammer station from the Bonus boss, its a quite rare drop.
Hardmode HS, correct?
I haven't really done any of the new hardmodes since i came back, so i wouldn't know what the desired gear would be to enter HM HS.
I assume it falls within the same category as Esseles/Black Talon, being that it's only the second Flashpoint you ever get to do in the game?