The price is kinda wobbly on this one as well as on the other genuine Shogun set weapons, mostly because there are only a few of them on sale(5 on outpost if I counted correctly).

For example, I just did some researching and easily managed to buy one for 2.33ref(Don't know if that was pure luck since the trade had been up for 15hours as you said BUT the guy who offered 2.33ref, didn't come online in time: http://www.tf2outpost.com/trade/6683346 ).

I also managed to find someone who has been overpricing this item like crazy but seems to have gotten some ridiculously high offers: http://www.tf2outpost.com/trade/6002465 (99% sure that both of the offers are from trolls but you never know.)

i'm not going to upvote/downvote for now, just had to clear some things up. Good luck with your suggestion.