There's a couple of sites in the UK offering this part for about £150
It's also called POWER BOARD,ASSEMBLY,OVC1000
Search Google using your long part number...
http://www.hasspares.com/shop/viewdetails.asp?Part=3117734008&ID=70151&CatID=4&BrandID=46
Alternatively a workshop electronics engineer may well be able to diagnose and repair your broken one - all the components on it will be easily available and cost little more than 50p each.
Good luck...
Pecavi
December 2012