Good question. I believe that the game at Wembley would have opened the eyes of the NFL merchandising dept and Reebok to the huge numbers of fans not only in the UK but Europe as a whole. This will have the desired effect and we will see the range of jerseys and availability expand.
There are quite a few internet based companies within the UK which sell Reebok replica jerseys. Reebok UK haven't been importing the premier or authentic as they haven't felt that the support for the sport was there.
It has the same feel as the late 80's and early 90's now as more and more people get into the sport and, as you point out, the TV coverage has helped enormously. With BBC1 showing the Superbowl to a national audience ( if they stay up that is ) we could see the sport in the UK expanding even faster.
Will you post a picture of your jersey from N-Fluke when you get it in the latest pickup forum?