Create custom WooCommerce account login form

We have a website using WooCommerce. We have also created "private" products for a specific group of customers. A new user "role" has been created called "SBTC". We need to create a NEW "account creation form" tailored specifically for this client / users so that the user role is automatically set to "SBTC", instead of the Wordpress "default". The idea is as follows: 1. SBTC customer creates a new account at [login to view URL] 2. The form on that page looks like the "standard" WooCommerce account create form ([login to view URL]), but it has extra code so that the user created is automatically set as a "STBC" user role. This really is a simple job for someone who understands Wordpress / WooCommerce. It's just about creating a form that automatically sets a user role. It shouldn't take any more than 30 minutes for someone with the right skills. Thanks.