I am traveling with Rocky next week although we are only going to North Carolina and we live in NYC i have bought him this carrier. It is a little higher than what Jet Blue's requirments are but it has this piece inside that i can snap off and squish the carrier a little bit down and it wont collapse on him.
It looks sturdy, well constructed and it was only $79 well after shipping and taxes came out to like $95 which is still not bad so check it out.
http://www.yorkietalk.com/forums/showthread.php?t=82393