You can get a 12R5 associated for around $250 to your door now. Then you just buy a second hand ESC and motor off this site if cash is low. Thats what i did and i love it. otherwise just keep an eye out for a second hand one.

like this:
http://cgi.ebay.com/Team-Associated-...item518ab55352

or keep an eye on this. only two days to go and cheap shipping:
http://cgi.ebay.com/Team-Associated-...item56364aaf20

otherwise for a bit less you can get one of these from stormer hobbies:
https://www.ssl-stormerhobbies.com/c...cs&pn=CFX12000
https://www.ssl-stormerhobbies.com/c...cs&pn=COR00056
https://www.ssl-stormerhobbies.com/c...=cs&pn=CRC3200

hope that helps.
Alex