The measurements of the old tilt latch are: Length: 2 11/16", width: 11/16", thickness 3/8". I tried one from Home Depot (Vinyl window latch (white) mortise installation, 3/8" thick housing, Model # F 2749). It fits in the window but is too long (won't let the window close).
Your assistance is appreciated (especially since the rest of the windows in the house are the same vintage).
John