What size spline did Certainteed use on their window screen in 1987?

Hello,

Unforutnately, we do not have a record of the hardware that Certainteed used for their screens. We also are not able to make out exact dimensions from photos. With that being said, you are welcome to look through the replacement screen mesh options that we carry here. 

You can also find our selection of spline here. I would recommend starting by reviewing the .190" diameter 59-190 foam spline, which looks like it may be a similar size to your part. Thank you!