I know we have a bunch of them in the office to work on routers/switches...
I would just go to Newegg.com I have spent over $6,000 from this site over 4 years and Always had great service/shipping/support/RMA from them. They are the best PC site on the web. i have a hyperlink here for the search dunno if it will work.
http://www.newegg.com/Product/Produc...al+usb&x=0&y=0