It requires a spring from a ball point clicky type pen, one M3x12mm cap head screw, an M3 locknut and a couple M4 washers (in addition to all the hardware listed in the linked model). It is posted here (but again it is not tested).
UPDATE 8-20-2021: I updated the latch after using the same design on a Pi4 holder (posted here: https://www.thingiverse.com/thing:4936218). I have not tested this model, but I did test the latch using the Pi4 holder and it worked there. I'm not planning to print this however, since I already have the non-latching version of this thing, which works OK for me. If you do print this please provide feedback. I suggested calibrating flow prior to printing this since there are dovetails and close fitting parts.