I've been looking for one my self mate, their not easy to find cheap, and if you DO find it cheap then be careful, as the ECU for a broken eberspaecher or wesbasto can cost £300 on its own. Which is why they sell it like 'was working when it was removed blah blah'. Theres some guys on gumtree selling refurbished kits for around £350-450 and others on ebay selling kits for £750.
Im thinking it may be worth going with one of those so I have some recourse if it stops working the first week.