Well, its $90 for the kershaw conversion:
http://www3.towerhobbies.com/cgi-bin...=LXYYD9**&P=ML
Or you can buy an ESC like this:
http://www.hobbyking.com/hobbyking/s...idProduct=8993
$59.95
And a motor similar to one of these:
http://www.hobbyking.com/hobbyking/s...hless_Inrunner
http://www.hobbyking.com/hobbyking/s...idProduct=6678
$30
So, $90 for the brushed system(plus shipping) or $90 (plus $15 shipping and $8 for a pinion gear) for the brushless. Not a huge difference, and the brushless would be a much better, longer lasting setup.
Not to mention if you sold your brushed setup you have now, then it would be cheaper to go the brushless route.
Thats what I would do. I think I will eventually do something like this on my Associated MGT once i get it converted.
Eric