Other companies make spud brackets these days. They're not terribly expensive. On the other hand, that's SCSI-only (with SCA connectors), so the drives themselves are expensive.

Edit: Hmm. A company called Silicon Gear used to make them, but it looks like they might be out of business these days. Also, assuming you can get to the drive physically without shutting the computer down, you don't need to power it down in order to swap out hard drives. It's not technically supported (actually, I think it has been for the last few years), but I've never had a problem doing it in the last eight years or so.