dsv424 - I think that piece is called the pivot arm assembly.
Here is a link to their parts section for the Classic Press: http://www.leeprecision.com/cgi/cata...476.5432=90496
it is listed as P ARM ASSM (SMALL / LARGE)
They have that part (if I am correct on the name) for $7.00
EDIT: If that is not the right piece, their phone number is (262) 673-3075