Hitec standard servos uses 2.6mm (2.5 will work). There micro servos use a 2.3mm. I had to contact hitec for a 2.3mm screw long enough to use the servo saver.
Your battery is probably fine, your reciever/esc is toast.
That's kind of what I was afraid of. Going to email them tomorrow and see what they say. I knew i was going to have to/want to replace them at some point anyway, but really? Thing barely rolled 20 feet.
And charged the battery again. Or at least plugged it in until light turned green and it operated normal again for about 20 seconds and then slowly died. No burning electronics smell.