182 cup pack driveshafts

[Edges]

I've read loads of old threads looking for info but... I need 2 new shafts and will probably get them from one of works suppliers (all vehicle parts) as they use shaftec who generally use genuine items refurbed.
My question really is what part numbers should I be looking for? Or is there a listed length difference between different shafts? Just don't wanna get the wrong ones

182 with cup packs by the way

Thanks