I should have mentioned 712's.....

From one LH to another - your first mistake was not learning golf as a RH (my first mistake was switching to LH 25 years ago after borrowing RH clubs forever). IF !!! Titleist still has one head leftover, that would be your lucky break. Otherwise you'd need to scour golf shops that may have sold an AP2 set minus the W. Iron Finder/e-bay may have one from time to time. The quickest replacements may be a 714 (51 degree) in place of the 50 degree 712 - or add a Vokey gap wedge. Happy hunting.