I'm sure I could put together a trip that would include Eton; the main problem would be whether the school allows visitors access. The best time to visit would be either the last day of school holidays or the first, I think. I'll contact the school and ask if it's possible.
Edit - The school office says no to visiting the chapel, so I asked if they had photographs of the various ABW memorials which they could send us. Was put through to the library and have left a request with them.
Does anyone know an Old Etonian who might be able to help? Might be worth asking Prince Harry.