There are a couple of early 1900s padlocks with the year on one side. I am trying to get a handle on what is out there. This one is 1901. There is another that will be posted shortly for 1904.
This padlock had a high bid of $18.08 (Plus $3.25 Shipping).
Antique 1901 America Padlock, no key, iron or steel shank, brass base, fine cond. - eBay (26 Aug 2010)