I get that these are designed to be screwed into wood, however, for a DIY project I need to add a nut onto the screw end. Would a 3/4 nut fit?

1/2" - 8 is the closest nut you'll find, but those are made for more square threads where this hook has a sharper, more pronounced wedge thread

The 267964 is designed with a very coarse thread (for screwing into wood). Unfortunately, there is no nut that accepts this type of thread.