Good
http://www2.towerhobbies.com/cgi-bin...&I=LXL370&P=ML
OK
http://www2.towerhobbies.com/cgi-bin...&I=LXSK07&P=ML
You should be able to find an equivelant at a well stocked hobby shop
Add another $10 or so for a charger unless you have one already that is capable of charging 12 volts at at least 250 mah or better.(you will need a charger even if you buy junk from a junk yard)