A quick learner from Top corners of the windows. says:
December 17, 2020
I wanted to add more photos but I couldn't.
Paul from SWISCO responded:
December 18, 2020
Hello,
We have two similar top sash guides with two holes, the 18-066 and 18-093, but both are 5/8" wide at the base. Take a look and see if one of these options could work for you. Thanks for posting!