My Kids and I discovered this gem by accident. It is NOT a camp site, but rather an ideal parking zone where many campers and T25s seem to show up. It's where they filmed some of "Game of Thrones"... here are the coordinates:
It's between the Carrick-a-rede rope bridge, and Giants Causeway... two great days out. There is a little beach and a massive beach a short walk away, with a great public pathway along the shore.
Here is a shot of us in the spot... it's a pano... so find the t25 on the right side:
It's about 15 min from Bushmills, and the coast road from there west has several beaches you can park and camp right on.