Thanks for the picture. AFAIK this supply wasn't used in anything other than the VK100 so that's the only source for a direct replacement.
Kludging something up with a modern supply looks fairly easy; there's plenty of room in there, but it will be ugly. Don't know what I'll do about the fan, but the VK100 logic itself probably doesn't need a fan so whatever is built into the ATX will be enough.
