There are a lot of great tuners out there. Many radio repair shops carry them. Here's a good website for reference:
http://www.fmtunerinfo.com/
Good Luck!
Mike

Rotel makes a tuner that does AM/FM/Sirius/HD, and Marantz has one that is AM/FM/XM.

There are a couple Magnum Dynalab XM tuners, but they're out of your budget, and I can't imagine they're worth the price, given the fairly low bitrates of most satellite broadcasts.

Polk sells a component XM tuner, as well.

You might also consider getting something like a Logitech Squeezebox, which would allow you to play internet streams and access online music services like Rhapsody and Pandora.