Talk to one of the regular ebay breakers, they must have a few by now.
Russ (ebay "squibs063") or Richard (ebay "landy-spare-parts") have both been through a few Disco 2's recently, I bought a complete manifold off Russ a couple of weeks ago from a D2 V8.
Both good guys to deal with, Russ is between Ampthill and Clophill, Bedfordshire, Richard is in Wallingford, Berkshire.
Peter