Hi, I did English A-Level under a different exam board, but we also did coursework. Honestly, researching and writing a quality essay was much easier when there were a lot of resources. However, note that you won't be using every single resource (it can act primarily to inform your argument), and that just means that you would need to interpret the text more yourself, which seems doable as you're already highly interested in the book. If you really like the text, do it (though I would recommend being able to access around 2-5 articles/critical essays on the text).
Hope that helps!