We can't find any source for this item (quests reward, drop, etc). It's highly probable this item is not obtainable right now.
Doesn't look like it has an extra stat for legendary like most named items...
any idea about if we upgrade this we get a legendary ?
This might work like other jewelry in Gen and Laz where upgrading to legendary doesnt give you a 3rd perk, but you can have it drop as legendary with a random 3rd perk