I bought a couple off of ebay and they were really nice, im not sure if they are authentic, but everything was stitched and it had the NFL logo as well as the Reebok tags. One thing you want to watch out for is that the jersey has the "redskins" stitched under the NFL logo. Some do not ie.
http://cgi.ebay.com/SANTANA-MOSS-AUT...QQcmdZViewItem
Also make sure you dont get one with the redskins insignia on the shoulder, those look really fake.