According to an old Wheel Goods Catalog, the correct brakes for a '64 bike would be an engraved version with 2 springs. It is pictured in the 2nd photo here:
http://pg.photos.yahoo.com/
Note that the '62-64 version used 2 springs, while the pre-'62 version used only 1 spring. After '64, Weinmann stopped engraving their name on the arms and used "Weinman 999" stickers.
One note, Schwinn had a reputation for buying parts in large quantity. So, a Paramount might have older components than its model year.
Scott Davis in St. Paul, MN USA
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