Factory Stock CD Changer for 99 Jetta?

[Khan Klatt <khan@mediaaccess.com>]

My girlfriend bought a 99 Jetta (GLS) but without the CD changer. Our
criteria for a new changer are the following:

a) Will take advantage of existing head unit. (changing discs, etc.)
b) Will take advantage of existing wiring and brackets, etc.
c) Doesn't cost a heck of a lot
d) Doesn't outclass the stock speakers (I have no intention of upgrading
the speakers so a world class changer is unnecessary since I'm keeping the
stock speakers)

What is the brand of the stock radio headunit? What brands/models do you
suggest to create a "seamless" setup. (For my 97GLX it was a Clarion
CDC635, for example).

TIA,

-Khan