If a 'Cheap Box Stock' class is the goal, then maybe a kit that includes motor, ESC tires and rims might be the way to go. I have been thinking along the same lines and thought that maybe a Tamiya TB-02 class might work well as an entry-level class.
Run the kit silver can motors, on fixed gearing with the included ESC. I know that RCMart sells several models of the TB-02 for under $80 USD. When you consider you get a Tamiya body, motor, ESC, tires and rims it starts to look pretty inexpensive.