what size diff do i have?

[badinfluence]

i have a 98 cc 318/5m,2wd,with a 12 bolt rear,and i recently shattered the yolk that connects the driveshaft to the diff.
i'm trying to track down what part i need but everyone has the diff listed in inches,and thats the part i'm unsure about.
does anyone know off hand what it is?
also,a decent place to order the part from?

even calls to parts shops and dealerships in the area have been useless.

[TurboBlew]

9.25


http://www.ringpinion.com/

[badinfluence]

thank you.