Archive Zephyr Scale Data

Hey, 

we are using a Data Center Licence for Jira including Zephyr Scale. For the future we are finished with the project but need to keep all information for a certain time. Since the current Jira is hosted by a supplier and we need all information in our own Data Center Instance we need to migrate it. On our own instance we don't have Zephyr Scale. 

What options do we have for storing all Zephyr Scale Data on an instance without this app? We don't need the data to be edited, so it can be view only but we need  so access it permanently. 

Thank you and BR
Charlene