I spent too much time looking for what this patch might be and didn't find anything. The only patch I found with an NS on it was for Nova Scotia, which I have a feeling isn't what this is.

With that said though, it's hard to say what this is. The lightning bolt isn't the same shape as the SS, but it is the same shape as a lot of military groups use. Who knows though. It could be a Nazi thing. They did use similar lightning bolts too I believe, just the SS one is quite different. It could still even be a reference to that, but trying to be slightly less obvious.