As far as I have heard, there has been no spool for a tb evo V, most people are still basically using the evo IV spool with some modification... (i think they use the gear from the evo V to get it to work. You will have better luck looking at the evo IV thread i think.
btw, tamiya has just been quite about those metals gears haven't they... sigh... although i think they may not be necessary... just cool to see how they can affect the drive train and will it truely make the car better