I just noticed that there is a Brad Johnson authentic jersey on ebay right now. It appears to be from his previous stint with the Vikings because it is made by Starter instead of Reebok like the current ones are. However it does appear to be very similar with the All Tackle-Twill sewn on letters, etc.

http://cgi.ebay.com/AUTHENTIC-BRAD-JOHNSON-ROAD-VIKINGS-JERSEY_W0QQitemZ8730512613QQcategoryZ24963QQrdZ1QQ cmdZViewItem

Unfortunately this one is too small for me at Size 48 so I cant buy it. But if it doesnt go any higher than it is now it is a steal to get a authentic BJ jersey.