HI philipp, i have a swash plate rotor shaft pitch control and rotor head from an old kyosho 30 SRT helicopter you can have for free, its just sitting in my shed gathering dust, the way i see it, it would be cool to see you build a fairy rotodyne,wanted to build one for so long,but wanted someone to go through the build first.
For pre -rotating i have the main shaft drive cog and bevel gear you can have as well, you could hide it all in the body.
Rickster3057.