I seriously , honestly once spent 5 hours driving around looking for those nuts.
Finally in ended up in a custom fastener place and hour away that makes customed sized nuts and shit for Gullwing Mercedes ( in a factory right near my house oddly enough )
They didnt have any and were amazed that anyone had used such a nutty size. They could make em for 64 dollars for 2. I um ...declined.
Then they asked "why did they use that size? , where they French?"
I said no, they are austrian.
Then they said "why do they hate thier customers? thats an awful size!"
Anyway i have some some where but put up a post lookin for em, someone made a shitload once.
I have some somewhere but i gotta find em.