Please just need a NUT ( sunroof)

[tino]

As previously posted and pleaded for help -- I need to replace the nut that goes on the sunroof motor assembly shaft located behind the plastic nut used to manually operate the sunroof. I went just about everywhere with the striped nut to get it replaced but no luck. Mistakenly called Mercedes thinking that surely they can sell me a replacement or at least tell me what the thread specs are --- BUT after waiting a couple of days their response was - to buy a whole new sunroof motor assembly at a cost of more then $800.00 Ca. ---- Mercedes Corporate service is -- well NUTS.
Can anybody please tell me the nut specs or sell me a replacement??? There must be at least one burned out sunroof motor out there with this nut in place.