Sometimes buying at BG Micro pays off. :D
I got their catalog today, and found this on page 8 --
Switching Power Supply (68W) - $7.50 + S&H
According to the listing, this is the same type of PS used in external drive enclosures.
Better yet, it's an inexpensive alternative to the usual $30 or more charged for the enclosure, and it's new.
Listen, my child... to the sound of one hand clapping.