The Corbin Russwin ED6200 Spring Left Hand 187F89 was used on the 6000 series rim devices. This spring is used to push out the latch bolt, and is one of two springs. The ED6000 Series was discontinued in November of 2015, but the springs are still available. This spring does not lift the cross bar, all of the lifting is done in the hinge case, if your latch bolt is not extending, I would make sure your cross bar is tight, but looking at the cross bar screw and tenion sub assemblies.
Left Hand Spring
Corbin Russwin Part # 187F89