[CR]Simplex Seat Tube Shifter Part Needed

My 1955 Chemineau's lever operated Simplex front shifter, the kind located on the seat tube, has a very worn inner  plate.  Does anyone have any i deas as to where to find a replacement?

Here is a picture of my 1951 Chemineau's front shifter. http://www.wooljers ey.com/gallery/v/david+l/front+shifter+and+crankset.jpg.html 

David Lester

West Hartford, Connecticut, USA

http://www.wooljersey.com/gallery/david+l/

http://community.webshots.com/user/tenordl

http://velo-orange.blogspot.com/2007/04/le-chemineau.html