FNG,
http://www.aircraftspruce.com/catalo...s/dchelmet.php
...$336...I ordered 2, and the shipping was $98.36. After
duty, I think the unit price came at at about £250 - I note
T******r in the UK are quoting £285 inc delivery. Not cheap
by any means, considering what you get for the money, but
they seem to do the job...as usual, once the term "aviation"
enters the equation, the price seems to triple....
Ed.