How can i access MAS api from the CRM (sales and marketing) product

Problem:
I need to know how to get the subscription_types (a marketing thing) from the CRM Rest API.

Longer description:
We use the Freshworks CRM application (which integrates both Sales and Marketing) and it comes with a REST API as described here Freshsales | Refreshingly new CRM & Deal Management Software (freshworks.com), but this API concentrates on the Sales part of the CRM application and it forgets and lacks the marketing part of the CRM.

I need access the list of the available subscription_types (or sometimes called email_types).

In the FreshMarketer API ( Freshmarketer API | A Developer’s Guide) it is /mas/api/v1/email-types , but i tried many paths and combinations on the CRM application, but could not find the correct path. Please advise!