I agree with the nickel consortium. Also, the original 3 would likely have been called a "Combo", according to the catalog, here:
http://www.vintagedrumguide.com/images/ludwig_sets/1963_ludwig_drumsets8.jpg
Nickel ages much differently than chrome, and has that light haze to it, rather than the typical "crud" we see on chrome. (that's the only way I can describe it)