I have a Xerox 3315 printer that doesn't give me the option of scanning to pdf. I would like to install Xerox Scan Assistant which should give me the option of scanning to pdf, but I don't see where it is available in Windows 10. Are there any other options? Some of the Windows 8.1 drivers?
You can install the Windows 7x64 and Windows 8x64 software and drivers, you just have to understand that they are not guaranteed to work.
Application wise they will for sure work though, Worst case scenario, depending on what you are installed, you may need to disable Signature enforcement.
And if the signature enforcement needs to be disabled, then the next massive Windows 10 update may break it and you would need to reinstall. (This happened with Windows 10 Anniversary and will again with Redstone 3 update) because they replace anything that is not certified to work automatically (Assumed to stop people from blaming MS for an issue caused by a 3rd party.)