Would any old LFR nut work, or would it have to be specially designed for the Kahler? I ask because I'm pretty sure I ruined the original one that was on a guitar I just bought by over-tightening it.... my bad.
you should measure the width of the nut that you broke, and see if you can find info on them online. if you can go to a store and find one there, even better.

i think they're usually 50.4mm wide.
I think I'll just have to order one off the Internet... can anyone recommend a good site?