If you are interested in a highly configurable RSC private server source that by default is authentic but can enable all sorts of custom things, check out Open RSC
There is a single player version that comes with everything pre-compiled as well:https://github.com/open-rsc/single-player
Feel free to keep in touch in our Discord: https://discord.gg/94vVKND
Open RSC is based on RSC Legacy's source that Moody released.
ORSC server source evolution:
RSC Daemon -> RSC Angel -> DarkQuest -> Moparscape Classic -> RSCL -> Open RSC
This is an open source development project and anyone is welcome to fork the code and do what they want with it. Feel free to submit issues and pull requests!