There is no such thing on the shelf since you need to know which rocker arms you are using as well as which lifters. Some lifters use a different cup size so you need to measure the lifter to see what size of ball is needed. Some rocker arms use a cup and some use a ball end. You also need to know if you are oiling thru the pushrod or not and you need to know the spring load and engine RPM range so you can figure out what diameter and wall thickness that you need.