https://www.projectsam.com/Products/Essentials-Series/1406
Either Orchestral Essentials 1 or go with Albion 1 by Spitfire (Bit more expensive but newer).
If RAM usage is an issue, maybe export certain tracks that are finished and import into a new session. Much less taxing that way.
Working in 48k instead of 96k sessions can help too, and closing any apps you don't need, particularly web browsers, they can take up like 1 gig of RAM usage.