I remember I tried to vote on this a while ago, and I came to the realization that you need to have multiple sales for you to have a range. My mistake, but I'll say what I said in my first attempt. Since there are only 6 if these in the world and it's a low teir effect on a robohats, sales are hard to find. Luckily, I did.

http://www.tf2outpost.com/trade/21406551

Here's evidence of the trade:

http://i.imgur.com/SLFwPY1.png

The Tavish's is a 1 bud unusual, the FIsts are 2 keys and the Manmelter was discussed as 3 keys, which adds up to 24 keys. 24 times 0.9 is 21.6 keys or 1.1 buds

Now, the Tavish's is were it gets complicated, because the price is old. That being said, I have some evidence of the Crown's value being maintained.

http://www.tf2outpost.com/trade/21911461

History:

#2866712583 -=CzS=- Roque

#2863095860 Hellraiser.exe

Link to Roque's current trade: http://www.tf2outpost.com/trade/21938746

http://www.tf2outpost.com/trade/21211117

Trade for the crown: http://imgur.com/upFSPLT