Finally

3 exists , 1 active

https://backpack.tf/item/4161648529

Sale 1 (2/4) 19

Sold it for Cloud 9 Backbiter's Billycock

https://backpack.tf/profiles/76561198043863705#!/compare/1522454400/1522627200

New suggestion : https://backpack.tf/suggestion/5abd0381cf6c751d0709279b (suggesting 18-20)

B/O from bot : 14.8 keys -> ~15keys , but it is duped

Sale 2 (29/3) 13

Sold it for Bubbling El Jefe

https://backpack.tf/profiles/76561198388910607#!/compare/1522281600/1522368000

Minis : https://backpack.tf/profiles/76561198155929872#!/compare/1522368000/1522454400

Sale 3 (17/3) 14

Sold it for $27.5 on marketplacetf

$27.5 / $1.98 = ~13.8keys -> 14 keys

https://marketplace.tf/shopitem/76561198054758757/30625;5;u57/Terror-Watt%20Physicians%20Protector

Sale 4 (15/2)

Sold it for 11keys + 18refs (key was worth 37refs on 15/2) = ~11.4keys -> 11 keys

https://backpack.tf/suggestion/5a77211a44325a0ee3501539

https://i.imgur.com/KJlRXTG.png

Sale 5 (8/2)

Sold it for only 10 keys

https://backpack.tf/profiles/76561197971983043#!/compare/1517875200/1518134400

Using 3 recent sales

{19 , 13 , 14}

Throwing 2 old sales

{11 , 10}

Taking final price at 13-19

Sorry for the big range

Old suggestion : https://backpack.tf/suggestion/5ab8f1c244325a2bba06ca56