immel: Thanks for giving us so much advice!
So out of fear, I was browsing Yahoo! Auctions and I saw this:
http://page10.auctions.yahoo.co.jp/jp/auction/m38553582
Are these two tickets that are situated from B5-D5? Meaning B5,C5, or D5? I'm not sure if I should take the risk and bid on these or go to the shop in Ueno (which I won't be able to go until two days before the concert).