If you've looked at what's out there, and it does not suit your needs, then you'll probably have to get someone to do what you specifically want.
If it were me, I'd check the usual suspects for Mk3 performance aftermarket. I think that all of the major vendors are pretty good about getting specs for their parts for you. If any of them do what you want, great. Buy that.
If not, then you'll have to get something made specifically for you. There are a lot of places that will weld up a custom turbo manifold. Some are probably better than others, but you can probably find one in your local area that does good work for a good price by visiting a few local meets or message boards and finding guys who have custom turbo setups under their hoods.
I didn't want to deal with that kind of stuff, which is why I got a turbo that fits on the factory manifold, and could use factory exhaust stuff. That way other aftermarket stuff fits directly on without everything needing to be custom.
I can understand the eBay manifold being junk, but i'd bet that there are good reasons why the other manifolds are the way that they are, and that it's to fit other parts that have to go around the turbo, like wastegates, downpipes, intakes, oil/water feeds and returns...