The Crusty the Clown hat usually comes with the points set. If the points set is handed, then it's usually stuck in place. If the points set is universal (can fit clockwise and anticlockwise CB assemblies), then the CtC hat is usually loose and easily lost. Best to stick it in place as the first job.
If you manage to source a new points plate, please let us know where from.
Most Lucas CB assemblies seem to run perfectly well without the CtC hat, although if the spring blade is loose, it will swing out and rub on the cam. Most even seem to run perfectly well without the spring blade.
Ken.