I need replacement latches for a window from a Larson storm door(older door)

this window is missing the right and left handed latches that hold the window in place and also allow you to change the window position in the door. I've spent a lot of time on google today and I've found such latches for sale but I can't find them now. One site showed a narrow spring I think goes between these latches, in the bottom of the door, that provides counter-pressure to make the latches work.