House was built in 1989. The windows are a G.A. brand. GA is on the locks.
Tom from SWISCO responded:
December 3, 2018
Thanks for posting. It's tough to say what will work without dimensions, but start with our 55-030, 55-202, and 55-212. One of these may work for you as a replacement. I highly recommend looking over our measurements just to be 100% sure.