A while back someone was asking about brushes for cleaning Jones plugs. I stumbled onto these in Harbor Freight yesterday. They are not brass or any other kind of metal.
They are just stiff cleaning brushes and the smallest one will fit inside the Jones plug holes.
https://www.harborfreight.com/airbrush-cleaning-brushes-5-pc-68155.html
There is also a GE part number to go looking for.