I ordered a replacement power supply directly from Shuttle USA. They said that is the only way to get one - directly from them. My model was $45 plus shipping.
For those of you who need parts that are not available otherwise, go to us.shuttle.com and click on the "Buy XPC Accessories on Ebay" link. Then click on the order by FAX link. The order form has the phone number. I talked to a guy named Sonic.
The folks at sfftech.com forums pointed me in the right direction.
Good Luck all!
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