Nova is the same as the first generation Camaro ('67-'69) the 60" wide rear is getting hard to find because they are being bought up by Camaro owners. The '70 up Camaro rears are 61" wide and have different spring perches. You want a 8.5 10 bolt rear out of a '72 to '76 Nova, Apollo, Ventura, or an Omega as they all had the corporate ten bolt with either mono leafs or multi leaf rears.
72 - 79 all had the 8.5" and they all have the same overall width and spring perch width, however after 75 it was only installed on V8 cars and in 76 only a 350 V8's. If you are close to me I have a spare from my 75 I would part with.
thank you guys this will help me out,if i go to the wrecking yard i`ll know what to look for now. Philip i live in southern oregon,how much for the rear end,what gears are in it.the shipping may be way to high.