Normalizing using RMS as opposed to Peaks.

[steve]

is it possible to get a Plugin or something to use within Audacity which can handle RMS Normalizing?

Yes, here: RMS Normalize

This is a “Nyquist plug-in”. Installation instructions: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_linux.html#nyquist_install