The first anniversary Sub's from 2003/2004 had a different bezel then the later one's!!
It is only a small detail but in my opinion that's a very important one, because they were only made for a very short time.
Take a look at the 4 from the 40 minutes scale on the bezel, it is flat and not pointed !
For me, there exist only one real true 50's anniversary model and that's the 'flat four' Sub.
best regards
Claude