The S15 head can be repaired. I'd recommend inquiring with your local machine shops. Feel free to send them the pictures. It's not a difficult operation. It simply requires the right tooling to "zero" onto the mating surface to the cam, then cutting any material that protrudes from the surface. I'm not sure what it would cost, so if you find out, please let me know. If it costs a lot and more than the head would be worth, then I'll just scrap the head.
Hello, we currently do not have an online store front but I am working on it. Its difficult though since we also sell our stocks locally in Japan so I'll have to be updating the website everyday.