Nice work! Of course it adds value to the overall piece (though i don't see that as being most important in this case) in that i would personally be much more willing to buy a sword with a scabbard than without. As long as you are always clear that this scabbard is your own creation i see no problem with it whatsoever especially since you did this as a carefully researched, beautifully executed and accurate reproduction. You should be very proud.
