After spending nearly a month online, visiting local bolt supply warehouses, etc., trying to locate the needed 8mm–10mm step studs, I finally found some–at my local friend’s garage. Why I didn’t check there first, I don’t know. Although, I do know more about them now than previously.
The problem with ordering them online is that it’s hard to justify spending $1.50 per stud and paying $10.00 in shipping charges. So, I finally have them. I also ordered a 10mm tap and drill set that hopefully will be here in the next few days.