400 GB Drives

When we bought our Xserve 9 months ago, we filled half of it with 400 GB drives, with the intention of buying more 400 GB drives when we needed the bandwidth / space. The need for bandwidth and space has arrived, but now Apple only sells 500 GB drives. Using those would totally throw off our scheme to keep the LUN's the same size, and would make a couple of the 400 GB drive we already have useless. So I ask you: Do you know of any company that still sells the 400 GB drives? Are any of you looking to sell some of your old 400 GB drives to make way for new 500 GB drives?

Many Mac OS X (10.4.5) Xserve, RAID, Xsan, you name it