You can find AQA A level Physics old spec papers here
AQA got rid of old specification Physics A-level past papers from their website, about a year after they last sat. This is just the way AQA do things, they only want you to access their current spec papers.
The old spec papers are still very useful for revision. There were one or two changes to the content to be aware of with the new spec, but the main topics, like mechanics and electric circuits, haven’t changed much if at all.
The old spec papers give you several years of exam papers to practice, whereas there are only a couple of years with the new spec.