Is it possible to get custom eartips for the Apple In-ear headphones?

A year or so ago I purchased the Apple In-ear headphones. I use them primarily in the car when my brother plays his music through the car stereo while I'm watching a movie on my iPod Touch or my MacBook Pro. They have very good isolation, but are uncomforable and it is very hard to get them to fit in my ears properly as well as keeping them from working themselves out of my ears. This is with me using the small eartips as the large eartips don't fit in my ears at all and the medium eartips make my ears hurt more than the small eartips along with not fitting as well.

I think custom eartips may be the best solution to my quandry.

Is it possible to get custom eartips for my Apple In-ear headphones?

If so, where can I get custom eartips for my Apple In-ear headphones?