Is the rattle inside the head or in the shaft ?
Suspect it would be in the shaft, so blow the grip off with a compressor and fish the offending piece out.
It could be a broken piece of the tip weight travelling up and down the shaft, then grip back on, fixed.
From memory I had to use two conjoined tip weights in each club to get the swing weighting correct.
Something your local pro should be able to do without to much fuss
I've given it a beating and can't get the ratte to go more than 4-5" up the shaft.
Will beat it some more