We are a NGO looking for something 99% similar to Stack Overflow for analyzing and suggesting improvements in legislation.

I have tried searching for terms and conditions for getting StackOverflow engine for sort of semi-internal use, and after much searching I by accident found this reply ( http://meta.stackoverflow.com/questions/60680/has-the-stackexchange-buying-option-been-closed ). 

The default answer that crops up all over the place is http://meta.stackoverflow.com/questions/16054/is-the-stackoverflow-engine-available , which doesn't actually say much, and the stackexchange site itself doesn't, at first glimpse at least, say anything about creating your own SE sites anymore, just lists the existing sites(?? or do I need to be logged in to see that option).

Anyway, our needs are with several exceptions to how Stackexchange sites generally work:

 1. The Question part would be actually a suggestion from an expert for a change in legislation, so initially at least, no questions from people with no rep;
 1. Initial majority of comments would be limited to the experts and such members that have received high enough ratings;
 1. There should be possibility to limit the visibility of suggestion for the public until it is approved (received high enough upvotes from experts);
 1. The site must be customizable in appearance AND in language (need ability to supply different language for labels & help texts).

Now, it seems SO engine might be able to do this(?), but this is, of course, not how SE sites work. Any solutions available?