Here is the rack you are looking for, but you will have to buy the entire bike.
Maybe you could convince therm to ship the rack.
http://www.ebay.com/itm/J-C-Higgins-SEARS-Vintage-SPACELINER-Ladies-26-CHROME-Bicycle-BIKE-w-SPRINGER-/362099026965?hash=item544ec8ac15:g:AeIAAOSwUmlTz6Ui