Additional Curse Veiled Mod

I've been tying to snipe this one for a very long time with no luck. I couldn't find any information about whether it has a certain item level threshold or a specific encounter it can be acquired from.
Anybody who managed to find this mod and care to share where?

It's an arbitrary-location ilvl75+ body armor mod.

I've actually unveiled it three separate times. Never found +1 totem on a shield though.

Buy a chest with +1 curse, scour it, make it a rare with open prefix, veil it with aislin in research, unveil again and pick your +1 curse craft - it will be learned