No worries 300-600...who do you fly for....didn't know anyone in the UK still operates those (Monarch)?
Found the US supplier of sleep master mask on ebay-com... if you are the west side of the pond it would be cheper to buy from them over here though postage makes it fractionally cheaper to buy on.co.uk...still expensive.Just bought another to cut out the snoring completely....but the Mrs didn't care for me wrapping it around her mouth!!!