Moving SQL Diagnostic Manager to Azure - Looking for Sizing Specifications

I am in process of putting together plan to migrate existing on-prem SQL Diagnostic Manager to Azure and am looking for suggested Azure sizing specifications vis-a-vie type of storage, Solid State RAM etc.  My current SQL Diagnostic Manager is 10.2.3 and we will be upgrading.  Current data base size is about 75 GB and I am monitoring 17 instances in four locations in the US. 

Anyone sized an Azure environment for SQL Server Diagnostic Manager?