1st of all, I'm dubious that this thing is "unopened" or otherwise unviolated. And, your "highly valuable rare" could be a Lifelace or some such.
2nd, why is this price so high?!? Yes, you COULD get a Black Lotus, just like you COULD win the lottery. At this price, you've overpaid even if you get another piece of the P9.
With the current bid of $510, you could buy the Mox of your choice AND get a set of Revised dual lands.
If I "found" it in my closet, I'd definitely sell it.