Sorry, but I'm going to offer you more choices, not less.
Are you talking about canalphones, which go way in and seal off the outside world, or earbuds?
The thing about canalphones is that how they will sound and feel to you is extremely dependent on the shape of your inner ear, which is very individual.
One place to look for comparisons is here:
http://www.headphone.com/guide/by-headphon...r-monitor-type/(There's also an earbud page.)
I haven't tried them, but many people here are fans of the Panasonics. I did try the Sony ex81 and thought they were pathetic.
You should add Shure E2 or E2c (one's gray, one's Ipod-white) to your list. Those provide a lot of isolation from the outside world. You can find them for around $75 US, which should still be within your budget. I have used and enjoyed the next steps up, the very good Shure E3 and the excellent Shure E4, though not the E2. I use E4 now, but they're about twice your budget.
The Etymotic ER-6i is also in that price range. Some people are totally sold on Etymotic, but I have no love for them, from their weird, fragile, noisy twisted-pair cord to their lack of bass.
There are fans here of the Sennheiser MX450--earbuds, not canalphones.
And headroom likes the Ultimate Ears, which are within your budget too.
http://www.headphone.com/guide/by-applicat...tudio-white.php