This is an accepted solution.
Karlie here from the Shopify Guru Team! I've looked into your question for you and I'm not seeing any apps that would have the exact functionality you're looking for. However, what you could look into using is an app that would allow you to block specific pages of your storefront with a password or a login. This would allow you to give password access to specific customers, which could be done by email.
The apps that I have in mind are;
If this isn't the route that you're interested in and you're looking for a more customized process then what you could always do is look into hiring a Shopify Expert. Shopify Experts are developers, designers, marketers and photographers who you can hire to help you with your storefront. You can check out our Shopify Experts, here.
I hope this has answered your question. If not, or if you have any further questions please let me know. I will be happy to help!
Thank you for the mention @Karlie 🙏
Just thought I'd mention I'm from Bold and if there are any questions related to Bold Memberships I'm happy to help!
Here's a quick video showing some of the things you can do with Bold Memberships.