Hey,
Electronics Exchange on the Rock Road (at Woodson) has tons of surplus 5v power supplies on their shelves. They are in the far left isle about half way down on your right. You'll need a 5v, 2amp unit. they should have some linear (as opposed to switching) power supplies on the shelf. You'll likely have to swap out the plug that goes at the end of the cord but that shouldn't be an issue.
The best one I've found down there is one that was used for a Lexmark printer. It is a big, beefy linear that sounds pretty darned good.
Bruce charges $5/amp.