Preview Upcoming Sale but allow only members to purchase

[dkinnaley]

Our products drop all at once every 4-6 weeks. Before a sale date, we preview the sale on our site. On the sale date we send a password to our Patrons and they can use the password to access the product they wish to purchase. Would Shopify allow for us to do something similar? I'd like to make a collection that can be previewed by anyone, but is only accessible for purchase via password on launch day. I also need to be able to support 150-400 simultaneous checkouts and 3-9 thousand concurrent visitors. If this is possible, which Shopify plan would I need?

Thanks for your help.