I've seen plenty of sales for these decks on UnitedCardists. Not sure if there are any available right now, but you would do well to check there before buying on eBay as they will without a doubt be cheaper there (I remember a few sales that had two WC's for $100).
In my opinion, sellin/buying white centurions is kind of pointless. Theory11 gives some away every other week in SNC's. When theory11 runs out of them, then you'll get more money for them.