Replacement spring assist slider deibert

Looking for a replacement slider for window. Part has T-shape plastic guide on bottom. Window has rectangle tab that engages and rotates with window when tilted back into installed position.
Top has small angle fitting to hold string. Inside channel is a long spring and pulley.
Metal channel is 34 inches long. Not including plastic T On bottom. 1/2 in wide and 1/2 in deep.
Has a code stamped. 34D
Window weighs 30lbs