They aren't hi-res, but there was a set released in 2009 that was 24 bit / 44.1 kHz FLAC. That's what I have, at least.
I definitely recommend getting the SuperSU binary and replacing kingroot binary if at all possible. Simply because ChainFire's SuperSU is open-source and can be reviewed, while the kingroot is proprietary and has ads and possible privacy issues. Fortunately, if you have custom recovery, you can simply flash a root zip from there and not worry about kingroot at all.
I am also on a Mac, and while compiling the custom recovery is almost impossible on a Mac (I had to do it on a linux vm), installing it should be very straightforward. Just install android tools to get fastboot and adb, and download the recovery image. It is easier on Windows with the included tools, but shouldn't be any moreso on a Mac, from my experience.
You only need those files if you are doing a custom recovery. You don't technically need to do a custom recovery to do anything else. You can install KingRoot, and then the other programs, and you'd be fine. Custom recovery lets you back up the system and data partition fully and easily, to your SD card etc, and lets you install unsigned zip updates. If you install the custom recovery, you can also easily flash a supersu zip and avoid KingRoot and its rooting process altogether. You can also just as easily install the custom recovery and never root or otherwise touch the system files at all. But having the custom recovery and making a full system backup makes it a lot safer to recovery in case you do something messed up. With the custom recovery available, it drastically lowers the risk of doing anything catastrophically wrong with the device, as you can make and restore from backups if you mess anything up. Of course, I still don't think that everybody should do it if they don't trust in themselves, but it's certainly not the bogeyman that many make it out to be. As long as you have good device backups, you will not brick your device. Hell, I have even flashed corrupted system ROMs and bad recovery partitions just to see what it would take to make my device unfixable. I haven't found anything that reflashing known-good backup hasn't fixed.