Here is a picture of a "Made in China" aftermarket one more recently found, alongside one of my original ones.
I cannot speak for other variations however my original ones did NOT have the "Century" mark. Another "used rotor" I have on hand, NOT from my example, DOES have the "Century" cast into it (no balancing weights found on that example though) FWIW, the "Century rotor I have, had a different looking hub than the originals found on my '67 (11/66) San Jose example too. I am sure the two rotors I removed from my example are indeed original, not any service replacement. My thoughts are the "Century" rotors may have been service replacements. Others may disagree.
(notice the horseshoe shaped balancing weights welded in, located on the inside, near the hub)