I have:

Here's a material version of the Apple iOS audio Airplay icon. I used the triangle from apple-airplay as the base. In doing so, I think the 1.5px rings in option "C" work best when compared to the 2px rings in access-point and option "A".

If we add this, we should probably suffix our existing icon with -video. Also, as a brand icon, we probably shouldn't be Materialising it; an official SVG can be found at https://developer.apple.com/design/human-interface-guidelines/airplay/overview/icons/
Personally, though, I think we should be deprecating our existing icon for v6.
I don't think this get named apple-airplay-audio, but some more generic. I also don't agree with deprecating the other airplay icon, because it really is very generic. It probably should just be renamed.
I wouldn't consider these Brand Icons. These are system icons in a different icon style other than Material. To include them in a Material library, we need to Materialize them.
We have Google's cast icon in our library. Maybe we change apple-airplay to "cast-variant" and this icon could be called "cast-audio" or "cast-audio-variant".
Renamed and added.
Most helpful comment
I wouldn't consider these Brand Icons. These are system icons in a different icon style other than Material. To include them in a Material library, we need to Materialize them.