Is there a compiled Windows binary for the Ripple deamon rippled available for download? I only found its source code...
No, but there is a guide to building rippled on Windows: https://wiki.ripple.com/Visual_Studio_2013_Build_Instructions
Note this, though:
We do not recommend Windows for rippled production use at this time. Currently, the Ubuntu platform has received the highest level of quality assurance, testing, and support.
That's probably why they don't offer a windows build - they want people to use Ubuntu. Perhaps you could use a VM - that's essentially what the Docker suggestion does anyway.