Any supercharger that will fit the SRT, will also fit the R/T, it just takes different mapping from the Diablo.
The Techo will run you $7000-$7500. It is a bolt on kit, very straight forward install. It uses a Twin screw supercharger with a air to coolant intercooler. It sounds great, just enough of a whinning noise to know something is there.
It runs at 6lbs boost.