The turns ratio is about what you mentioned.
The issue is impedance and total power delivery.
You get an offset of voltage in one direction, and
current in the other. The radio itself won't really
need to drive any more current because it sees the impedance
it wants to see.

The answer is yes - it works fine.

The "low cost" approach to the flight is a good question.
The in-ear headphones are priecy - they ran me about $150
and are quite good.

BUT! That's part of my profession in the music industry.
Throwing another amount out wasn't really in the cards.

I am going to purchase a mic. I actually have one, but
can't get the schematics - and since it is powered, I have
to be careful.
I bought an old StarSet series, and can't for the life
of my se the schematics - it ha a dual plug for the headphone.
I'm going to remove that and just use the mic.
The headphone is more for quite-cabin use.

My headphones are very comfortable and have maximum isolation
for "non active noise reduction" type headphones.

Thanks for the follow up!

Gary