NOTE: Overpay in unusuals is factored in my calculations. Best offers are typed in bold font.

Link 1

http://www.tf2outpost.com/trade/10053404

• 1 week old.

B/O: 2.66

Notable offer(s):

O. Planets Anger if he adds sweets (~Maybe lower than 1.9 = ~1.8)

O. Fire Vintage Tyro + 3 keys + 4 refs (~1.9, using conversion of 1 bud = 22 keys at time of offer)

Link 2

http://www.tf2outpost.com/trade/9948197

• 2 weeks old.

B/O: 2

Notable offer(s):

Sold for Max (~2 at time of offer)

Link 3

http://www.tf2outpost.com/trade/9840682

• 2 weeks old

B/O: N.A.

Notable offer(s):

40 Keys (~1.8) (Trade owner wanted to take this offer but got retracted. Reason: Person has low stock in keys)

Link 4

http://www.tf2outpost.com/trade/9008988

• 1 month old.

B/O: 3.5

Notable offer(s):

Bubbling Heavy Duty Rag + Earbuds + Bill's Hat + 2.5 keys worth of sweets (~1.8, using conversion of 1 bud = 27 keys at time of offer) (Sold to this offer)

Average: 1.8 pures.

Highest offer reached: 2

I'm going to set the range to 1.8-2.1, as trades with b/o of 2 got offered 2 pures quite easily.

So, 2.1 should be reachable with some patience.