i there,
i had a quick search for you and here is what ive found. This cooler is resonably cheap and from a reputable brand.
http://www.amazon.co.uk/Arctic-Cooling-Accelero-L2-Pro/dp/B002C6EL4Q
it does not say much about compatibilty but from one of the user revews i saw that someone else has been using it on the 440 with no problems. I would give it a go for such a bargain price!
hope this helps
Regards
Jake