We are resellers. They don’t make it easy to find the Workspace link, but you can do it this way.
Go here. https://go.getproton.me/aff_c?offer_id=50&aff_id=5239
That will take to a deal for Proton VPN.
On that page, scroll down to the section called “Choose a plan and protect your business.”
Click the option on the right for Workspace Standard. It will show the discounted rate of $12.99.
They apologized to us — this deal is so new that the links aren’t totally set up yet.