I do not think that the car manufacturer has developed unique fasteners for a particular car, and now it is impossible to find something suitable. It seems to me that you're probably missing something. Try to measure the diameter of the fasteners on your car and find on the Internet a table of the dimensions of the fasteners according to the diameter. After that, you can look for fasteners in online stores and contact consultants if you still have doubts. I think this way you will certainly find what you are looking for.