Found some trackable sales for you.

1)

Seller: http://backpack.tf/profiles/76561198083328505#!/compare/1470614400/1470700800

Buyer : http://backpack.tf/profiles/76561198087853188#!/compare/1470441600/1470787200

Took part in bulk sale for Blizzardy Storm Troublemaker's Tossle Cap. What?

2)

Seller: http://backpack.tf/profiles/76561198087853188#!/compare/1470960000/1471046400

Buyer : http://backpack.tf/profiles/76561198030050182#!/compare/1470960000/1471046400

Sold 1:1 with Morning Glory Bolted Bicorne. What, what?

3)

http://backpack.tf/profiles/76561198030050182#!/compare/1471910400/1471996800

Sold 1:1 with duped Haunted Ghosts Ye Olde Baker Boy.

Not using this sale now. Will be used to make a mini-suggestion for the Baker Boy later.

4)

Seller: http://backpack.tf/profiles/76561198090956917#!/compare/1470096000/1470182400

Buyer : http://backpack.tf/profiles/76561198117326723#!/compare/1470096000/1470182400

Bulk sale.

5)

Seller: http://backpack.tf/profiles/76561198202339421#!/compare/1471305600/1471392000

Buyer : http://backpack.tf/profiles/76561198175893725#!/compare/1471305600/1471392000

Sold 1:1 with Bubbling Tough Stuff Muffs.

X = 36 keys.

6)

http://backpack.tf/profiles/76561198175893725#!/compare/1471478400/1471564800

http://www.tf2outpost.com/trade/28423732

Sold for Vivid Plasma Bombing Run + 16 keys pure.

Capped at BO of 33 keys.

7)

http://backpack.tf/profiles/76561198119634347#!/compare/1471996800/1472256000

Probably sold 1:1 with duped Silver Cyclone Taunt: Battin' a Thousand.

X = 23 keys (outlier).

8)

http://backpack.tf/profiles/76561198095022965#!/compare/1472256000/1472428800

Bulk sale.

9)

Seller: http://backpack.tf/profiles/76561198020674825#!/compare/1471651200/1471737600

Buyer: http://backpack.tf/profiles/76561198119634347#!/compare/1471737600/1471996800

http://www.tf2outpost.com/trade/28427021

Sold 1:1 with Pro. KS Aussie Scattergun.

Capped at BO of 30 keys.

Summary: 30-36 keys.

PS: Thank you, Jarool.