State schools are not funded by the government to offer them, so they cannot afford it, but I think independent schools can offer them - at least they can do IGCSEs, so why not IA-Levels? They tend not to, but perhaps that's because they are (at least perceived to be) harder than regular A-Levels.
If you pay for them as a private candidate at that centre, I don't see why not, but I'm no expert on this.