While an OEM license doesn't allow you to use it in a VM, there may be other reasons why you might want the keys. The following are how to access this value from a Windows system and a Linux system.
From How-To Geek and nixCraft:
Using a command prompty with admin privileges (per How-To Geek, nixCraft doesn't mention needing admin) on Windows…
wmic path softwarelicensingservice get OA3xOriginalProductKey
The original articles cover extra topics as well. I just wanted my own instructions on how to do it in case they linkrot away.
