I have Lawson windows from 1999.
This looks somewhat like the 18-201. Hopefully the necessary dimensions are close enough.
From the front the top is 7/8" and length is 1-7/16" overall. The screw hole is 7/8" from the very top or 13/16" from bottom of top header. The top notch is 1/2" from the very top without missing tang.
From the side the top is 1/2" and the top notch is 7/16" and the bottom section is 5/16".
Thank you.
William
