I think I ripped up all the skid plates on mt 450i last week on a survey job, haven't looked hard, but I see and hear a lot of curled up plastic dragging.
I know one option is to but a new set and use it as a pattern to cut some out of sheet of plate metal, I would probably glue the oem plates to the metal plates and have the advantage of plastic that slides better over stuff with the strength of metal
but, I'm hoping someone has already done that and make a product I can just purchase and bolt on