Hey, I've got an Action Replay Max for the PS2 here. I'll let it go for £6 which will include postage. I'm willing to send first if you have an above par reputation.
The model I have can be seen here: http://www.amazon.co.uk/Datel-Direct-Ltd-Action-Replay/dp/B0002LHSV6
It comes with a free media player CD, which is quite useful. It's in as new condition.