I would to create another store under my first shopify account. The second store will have the same products as like the first one.
But product prices will be different
As for today, Shopify allows only 1 store per account. With Shopify Plus you could get 9 extension stores.
Your best choice would be to create separate stores on different accounts and use an App like Syncio, in order to be able to manage all stores from 1 account (interface).