I'm not sure if Hostrocket even supports HTTPS on the service AGN uses. Since PureZC uses Linode (a VPS provider) assuming they are not buying shared hosting from the operator of the VPS acquiring HTTPS can be done using an automated Python application called Certbot.
That said, the warning in Chrome will be phased in, at first showing a warning whenever a password field is detected on a non-secure website.
There is already a flag in Chrome which will if enabled display a red triangle next to all non-secure websites.