Hey @AnnaRocks !
Ohad here, from Zoorix.
Just in case you are still looking for a solution here, I think that Zoorix might be able to answer your requirements. Zoorix supports multiple offer types including volume discounts, regular bundles, mix & match bundles, and more tools that can help you sell more. You may have a look at what the app has to offer on our website - https://www.zoorix.com/features, and also on our demo store - https://zoorix-store.myshopify.com.
I hope this helps and don’t hesitate to reach out if you have any questions or need assistance.
Cheers!
Ohad