The part in the pictures is 5/8 inches wide for the part that goes into the track and the total length(including the cap which is about 2/32 inches) is one and 3/4 inches. the total width including the cap is 7/8 inches. I could not find a match in your catalog.
Casey from SWISCO responded:
March 21, 2017
Take a look and compare the measurements to SWISCO part number 18-161 , Top Sash Guide.