Dunno where you got that info from. The kit is $2400 + $400 for the installation kit. I haven't heard of the computer being sold separately.
If you just wanted the computer with the timing controller, it would probably need to be a custom thing. The computer is supposedly custom programmed for each application, and as far as I know has never been used without the supercharger. The computer install was actually one of the hardest parts of the supercharger install, as it involves tapping into about 25 circuits in the X's computer and electrical systems.
As for the fuel, it would be easy to add a secondary FMU like I have. It is connected via a vaccuum line to the new computer, but I don't know if that's necessary. The FMU is made by another company, forgot who, for BBK. You could probably find out who and buy directly from them, or from Jegs or Summit or something.
Good luck!