tractor for little girl

[cosworth34677]

posted this on another site but same info .....

i am going to make a side project for the niece she is 14 and love to drive the trucks. but now since i kind of moved on to constuction she just watches looking sad. so im thinking of making a quick tractor so she can play when im out at the park with the nephew and her.

this is what im thinking.
http://www.ruralking.com/bruder-cate...tor-02444.html

so im thinking four servos a bec (witch i got) and a small 7.4v lipo and a 4 receiver for my 9x .

the question is what servos to use? im really bad at picking servos. the ones im using on my excavator are a little to week. i want something cheap easy quick and strong. this is for a little girl. im going to let her paint it and such (i so hope not pink) any help thanks guys