Just chiming in to say I found this recently and found it a really useful base. I don't have an RGB LED on my NN clone, but I forked it to work with just a single LED (using blink patterns/speeds). It's awkward, and a coloured LED would be way better, but better than nothing! Thanks for posting
Glove80 is probably the best commercial option, but is very expensive. For the combination you are looking for, DIY might be a good solution, depending on how adventurous you want to go. Linear choc/low-profile switches are not loud, but hard to silence. If you want silent, you'll need to tape mod and lube them (search up how). That isn't difficult, but is time-consuming. If your time is too valuable, there are sites available where you can pay people to do it before sending keys to you.
I recently designed a super easy-build portable board that I put together in an hour, for $80 and only very basic soldering skills. Shipping takes a while though. The low cost comes from having few switches/keys and using a chinese microcontroller. If you aren't ready for that few keys, there are options like the kyria or Lily that are bigger.
For portability, I'm just in the final stages of completing this 3D printed case generator that holds the two halves of a split keyboard together magnetically, protects the PCB, and has quick-unfold tent legs that you can customise at design time for your desired tenting. You could use this for whatever custom PCB you chose.
I use KeyMapper to map "long press of the lock button while screen is locked" to the lockdown/secure lock action
Adding to this, if you go with a pcb custom, then the keeb snakeskin cases are great for portability