Sorry Bert, these are not called heim joints Heim joints are like rod ends that have a spherical ball joint in them What you need are rod ends The plastic ones are no longer available The other short one that screws into each other are also NLA You can buy just the rod ends from peirce manifolds or Partsklassic ( Porsche shop ) You may have to make up something to work for you I make linkage up all the time but you do need a couple of dies to ( L & R ) to cut threaded rod from 5mm straight steel rod
Thanks, Rick