Just get in touch with one of the currently running NXT clones like NAS, NFD or NTX.
They have running systems already, and because they are NXT-based, you can build whatever else you want on top of them, just as you can with NXT itself.
This approach will save a lot of time on building a new NXT clone from the ground up, and allow you to just work on the extra stuff that makes your plan unique.
Good luck....