You can parts direct at www.racing-cars.com/usa.
or visit the various sponsors on this board (SpeedtechRc, KTHobbies)
I run the Mi2 stock outdoors except for the following items:
- Gear Adaptor so you can handle standard gears
- Pdubracing bumper to replace the standard one so that you will save your arms.
- if you race stock and 19T, the stock plastic bones work fine, to run modified you will need the steel fronts and Ti rears
To run indoors, I have all of the above with the addition of:
- Short front and Rear shock towers
- alloy rear hubs ( for better adjustment)
- I have not tried the stiff chassis but I don't believe that I need it for stock and 19T
The current shocks are a pain to build compared to the Tamiya, but you should not need frequent rebuilds and like all things, you can get the hang of them after a few times and its a non-issue.
You have the option of diff, one-way and spool for the Mi2. The diff is standard and all that I use.
The only other item I intent to purchase are the spaces for the rear for
Thats about it.
If you plan to run at the club/local/metro area then there is little that you need.