Thanks for that. I can find the discs that look to be right on their website. Though I can't tell exactly what the thickness is of the part the bolts goes through, and I can't seem to find any price or means of ordering.Try to find some motomaster ones. They are the same thickness as OEM, and come with attached bobbins/rivets.
Motomaster is a brand from the Netherlands and well know in the motocross world. I believe they advertise as "made in the Netherlands"
Part number for their discs is 111073, at least for the 2006 GS it seems to be. https://www.moto-master.com/