of course for the 64 bit drivers there is the little matter that they need to be codesigned.
That costs money to buy a signing certificate from a Microsoft approved certificate provider.
But once you buy it, you can use it for anything. Costs between $75-$125 a year.
Once signed, a particular driver is never affected if the certificate should expire, though, unless you want to update a particular driver. Then it needs to be signed again with a valid codesign certificate.
32 bit drivers are only partially affected because on a win64 system 32 bit stuff runs in a kind of virtual machine called windows on windows or SysWoW.