well notoriety is the key to high price jungles. there are a few lines out there that produce some spectacular jungles and i'd say the most well known ones are the ones that will command the highest prices... if you were to look for some high contrast babies with nice looking parents though you may be able to get a real stunner for like $150 from joe shmo at your local herp show.
andrew hare and australian addiction are two places that come to mind that have super high quality jungles though, so i'd check with them on prices. additionally there are some other BP.net members here that have some great JCP's too.
a quote i recently saw... "good jungles aren't cheap and cheap jungles aren't good!"