Update:
I managed to get a new bone nut installed on my Andoer maple Telecaster neck, had to use a square needle file to deepen the existing nut trench a bit because the nut was sitting a bit too high, I used some PVA wood glue to glue the bone nut in place, the neck is all ready to be installed on the body, which is due to arrive in the post by March 6th, I'm hoping that I can finish building the custom Telecaster by April if nothing goes pear-shaped in the meantime.
New bone nut installed: