for 2-3268, the way i read the table you posted, it says 1/4 head, which if you reference the top table it says 1/4 head = .48" diameter. which is also the same info the lady gave me over the phone when i ordered. additionally they fit the visor bracket i tested last night, unless i was imagining things.
And correct, there is a $20 minimum, so i ordered extras. I can double-check tonight if needed