I've pointed this out before, but I'll say it again: yes, you CAN embed fonts for the iPad. See
my blog post for the general how-to.
Now, just because it's possible doesn't mean you SHOULD do it. As everyone has pointed out, embedding support in different readers can be hit-or-miss (although I believe the method I posted should work in most cases). Also, it shouldn't be used for full text. For headings, such as you propose, I think it would be fine.
Still, images are generally the most portable solution. I would recommend creating the image at high resolution and giving its size in em; that way it should scale along with the font, and even if it gets big you won't see any pixelation.