Scott Bryan
The original ballcocks are available for the American Standard 2003 toilet (N3045). The replacement depends on if the toilet has a “vent-a-way” assembly in it. Here is a link to the complete parts breakdown fot the toilet. We stock all the original parts for your toilet if you have more questions use the link on the parts page to contact me.
Good luck,
Scott 
http://www.plumbingpartsdepot.com/asluxor.html
