Audiobook (Full cast) Question

Looking to buy the new Audible Harry potter books - full cast, entire collection for my partner for part of her birthday present, i am just wondering is there any way to get them on a deal or slightly cheaper? I know the first one or 2 is £22 ish and then the last 5-6 are around £37 each, i am sure they are worth the price & will pay full if needed. I just want to check theres not a full collection deal anywhere or a way to lower the max price through audible sub etc, any help appreciated :)