Guy Byars wrote:

Given that this is a comfort issue and not a safety issue and is only for a
passenger, are there any other cheap portable OX systems available. Medical
systems perhaps?

http://www.probuy.net/products/OXYGENPAC.html
http://www.avweb.com/news/aeromed/182584-1.html

George Patterson
Some people think they hear a call to the priesthood when what they really
hear is a tiny voice whispering "It's indoor work with no heavy lifting".