Looking for great UI samples for inspiration

Hi Indie hackers,

I'm looking for inspiration for a piece of UI I'm about to create for my product.

What I sell is a full-blown course that is divided into modules, each module itself being divided into a bunch of lessons.

I provide a single recurrent subscription for global access, but it's not working very well, and I would like to test a payment "à la carte" where a user could pay for a single module.

I would also like to provide some "module packs" where a user can buy several modules at once for a better price.

There are of course countless sites that work that way, but I've never came across one that made me say "wow" with the cart and payment ui.

Does anyone as some interesting links that I should check?

Thanks!