VL to VS Commodore rear shocks will "fit" the rear of a KE70, but do some research before you choose as there are many different shock lengths available for all those models of Commodore. They will all be super stiff in a KE70, but I'd say the FE2 versions would most likely be the stiffest.
The rear springs out of a Commodore won't fit in the rear of a KE70 properly unless you cut them, and then they won't fit properly because you've cut them. Try looking for some AE86 lowered springs.