8 month old price!

Sale 1:

Sold for Stormy 13th Defiant Spartan (7.5*0.9) = 6.75 (rounding to 6.8 buds)

http://www.tf2outpost.com/trade/25283746

Sale 2:

Sold for Dead Presidents Robo Gibus (7.2*0.9) + 12 keys (12/12) = 6.48 + 1 = 7.48 (rounding to 7.5)

http://www.tf2outpost.com/trade/25058386

Sale 3:

Sold for 2 Max's Heads (3.3*2) = 6.6 buds

http://www.tf2outpost.com/trade/25113501

http://backpack.tf/profiles/76561198100334597?time=1424246400 → http://backpack.tf/profiles/76561198100334597?time=1424332800

Sale 4: (outlier)

Sold for Professional Australium RL* (4.72*0.9) + 9 keys (9/12) = 4.248 + 0.75 = 4.998 (rounding to 5 buds)

http://www.tf2outpost.com/trade/25078645

Sale 5:

Sold for Stormy 13th Salty Dog (4.4*0.9) + Stormy Storm Bomber Bomber (3.15*0.9) = 6.795 (rounding to 6.8 buds)

http://www.tf2outpost.com/trade/25002280

Mini-suggestion for Professional Australium RL*: (after tax)

~$144.99

~$135.01

~$138.26

~$132.70

~$120.60

~$150.00

~$149.40

~$160.87

Average price is approximately ~$141.48. Valuing this at ~4.72 buds.

Notes:

For valuing the Earbuds and Max's Heads, I'm using the price at the time of sale.

http://www.tf2outpost.com/trade/25078645 - B/O of 85 keys (~7.1 buds)

Conclusion:

Sales at 6.8, 7.5, 6.6, 6.8 and an outlier at 5 buds. Taking a final range of 6.8-7.5 buds.

Feel free to support/counter my suggestion!

(credits to A Delicious Cashew for providing the sales!)