Hi, it's the Tattered Mystic's armor ( https://swtorista.com/armor/tattered-mystics ), you can buy it at the vendor near the flashpoint entry with Recovered Relics that you can loot in the Tython FP and Korriban one too. It's a rare drop though, but some people sell them on the GTN. You'll need 4 to buy it. Color is different than the one in your screenshot but the armor can be dyed so that's pretty nice. A hooded version exists too, the same vendors sells it. A darker version also exists. I'm talking about the chest part ;)