Confirm front disc specs

[Airwolfie]

I have a 81 US special, but the front wheel is off I don't know what. I want to get thinner and slightly larger discs, so I need the specs for the disc.

This is what I THINK is right:

Inside Diameter: 64 mm
Bolt Hole Circumference: 80 mm
Bolt Hole Qty: 6
Bolt Hole Size: 80 mm
Outside diameter: 289 mm

Can anyone confirm this is correct? I may have found some on epay, but I need to know before I click to buy.

Thanks guys!