On the window balancer (see photo attached) reads "13 3 ER CALDWELL"
The metal part measure 14 inches, both the top and bottom has wings (wing length 15/16 inch). Top part height measures 1 1/4 inches, bottom height measures 1 1/16 inches and depth measures 1 1/16 inches including wings and 1 inch excluding wings. I am guessing this might be a series
s385 judging from your guide. However, the top part looks slightly different. Please advise, thank you!