Subframe seat retainer nut 2011
 

Is there a replacement part for this? Or does the little rivetted in holder just drill out and you replace the nut? None of the parts diagrams actually give a part number for it, but 2011 shows it as a separate part...

You have to drill it out and replace with a RivNut.

Got a box of them so that's ok. Only concern is no nyloc?

2011 has a black plastic washer under the seat pan that is a tight fit on the screw. It acts as a screw retainer. Unless I'm mistaken there is no nylock on the riveted nut assembly.