I have an XPS 13 (9343) that was sold with Windows 10 Home. I've since wiped the hard drive and I'm trying to reinstall Windows 10 by creating installation media from another PC. All goes well but Windows will not activate:

Activation failed because this device doesn't have a valid digital entitlement or product key. Error code: 0x803F7001.

I don't see any option to download OEM installation media for my laptop and I have no recovery partition to reinstall from. What do I do now? Microsoft's website suggests that I need a new license to activate my copy of windows which can be obtained by entering my product key. Where do I find my product key?

Thanks,
Clinton