I'm sorry, but I have to say this:
How could you possilbly be so cheap as to not be willing to spend $10 for a stock AMD HSF!???? You're crazy if you think a P3 cooler will keep a Mobile XP chip cool...it's asking for trouble. Think of it as a $10 insurance policy for your $300 rig.
Also, why would you buy a mobile chip if you're not going to overclock it? It makes no sense to me. Save yourself $10 and buy a retail 2500+ chip, and it will come with the stock cooler, saving you another $10.