I'm not sure of the window brand. Perhaps Milguard, as the stamp between the panes says "GDP CALGARY AB IGMAL 15 MAY 2001 428313 US LR19 10". If I Google that it comes up with a link to Milguard.
Casey from SWISCO responded:
January 29, 2020
Have a look and see if our 38-2077 multi-point locking handle would make for a good substitute.