How to Find Epson 7800 Pro, Missing Control Board?

I have acquired a Epson 7800, a0, 24 inch, beast of a thing. It has a fault which I have tracked down to a dodgy maintenance tank control assy, part 658 from the parts manual. Fairly old printer now but can still produce stunning results, and at 3k new it is far too good to throw in the bin for a part costing a few euros. Does anyone know where I might source one in the UK or Ireland?