What did it cost them to get rid of Silver?

I'm not sure what you mean.... chapter please?

Chapter 24

I do not think this is the right chapter. In Chapter Twenty-Four, this is the only mention of Silver;

I remembered what Silver had said about the current that sets northward along the whole west coast of Treasure Island, and seeing from my position that I was already under its influence, I preferred to leave Haulbowline Head behind me and reserve my strength for an attempt to land upon the kindlier-looking Cape of the Woods.

I don't know what you mean