Is this what you need? Taken from the rig rite site.
NB1 Gooseneck Ball & Clip Kit: NB1-5K:
Gooseneck Ball and Clip Kit includes 2 each of both components listed below,
NB1-5 and
NB1-6. Kit has everything necessary to connect Gooseneck Casting to Mast Bracket casting (
NG1-11X).
NB1 Plastic Ball Half: NB1-5:
Plastic Ball Halves (2 required) are held together by (2) SS Spring Clips, and function as gooseneck swivel.
NB1 SS Gooseneck Spring Clip: NB1-6:
SS Spring Clips (2 required) are used to hold plastic ball halves together in Old-Style gooseneck.