I haven't tried one on a 2500 but it should be fine. However, not that it has a 70mm fan and is rated for the XP2600 and up.
Have you looked at these? For what it's worth they claim to be suitable for CPUs up to an XP3200.
COOLER MASTER CP5-8JD1F-0L for $12 and rated up to XP3200.
Or this one...
Speeze Falconrock for $14.00 and fee shipping. Looks like the same product as the CP5 and also rated for CPUs up to XP3200. Both have 80mm fans and are pretty quiet.
I've used the Falconrock with AS Ceramique on an XP2400 and it runs near 38C under load. You should be fine with any of those if you aren't planning to OC.