How do you get gold charms on runescape
They're a members only item so you must be on a member world.
You can get the as a drop from monsters, random event gift reward; or Soul Wars reward.
Some monsters that drop them are:-
Ice giant, Ice warrior, Ice spider, Fire giant, Rock crab, White wolf, Infernal Mages, Dagannoth, Black demon, Giant bats, Red dragon, Jogre, Ogre, Aberrant Spectre, Green dragon, Mutated bloodveld, Black knights, Jellies, Hellhound.