help with a edelbrock 1405 missing part

I'm not sure that little ball even comes with a re-build kit? You could just ask to look at a re-build kit from your local parts store to see if it does. And most the time the part stores carb re-build kits are cheaper then say Edelbrock's re-build kit. If you have an autozone or Napa in your area I bet one of there kits would be around 15 bucks.