We marched almost that well when I was in the Navy 1960-65.  Apparently there are some re-inactors who get into the spirit.  It is possible ($$) to purchase reproductions of all the pouches, belts, etc.  Also parts and new production stocks for the Lee Navy. 

But there were problems with the striker.  The Navy or Marines obtained modified bolts somewhere along the line.  I have seen rifles described as having a modified bolt.  Reading about the guy who had a striker penetrate his eye and then his brain took all the fun out of the Lee Navy game.