So it might be worth giving it a try?
No because you would be breaching license terms.
They should not be flogging OEM licenses to punters.
Not only does it breach OEM license terms BUT for an OEM license to be fully valid, it requires a Microsoft sticker to be affixed to hardware (or if you're a large player like Dell or HP, you can do fancy BIOS stuff).
Finally, just for the cherry on the cake, Microsoft don't even provide an "OEM keys by email" service to partners ... its either hard-copy or volume licensing via the VLSC portal for business customers.
I would say barge pole.... touch... do not.
From the horse's mouth:
Individual OEM System Builder Windows software licenses must be distributed with the following:
Certificate of Authenticity (COA) label
Hologram media
Documentation
Software License Terms
So that is the package that OEM System Builders receive from Microsoft distributors, and to make their installation fully legal, the OEM
MUST affix the COA to the hardware they are building for the customer.
Also note they don't even provide their full address on their website, only "London" and their postcode !