Cremax/IcyDock makes good drive housings from mobile bays to hot-swap cages. I've not heard any significant negatives on them except the SCSI ones can be difficult to set up as some of their manuals are not as clear as they should be.
Check this and see if something here couldn't serve your needs at a lot less cost.
HDD Cages. Of course you need to let your application make the call as to which is more suitable.
If you decide that the Icy Dock unit is the one for your application, then SCSI4Me.com or CensusPC.com has the best prices I've found. You'll have to see which has the best bottom line (ship + tax included) for you. I've bought from them both before with good service.
.bh.