First id run a bore scope down it. If the bore checks out I'd touch up the crown and see what happens. I would want a sub MOA rifle as well since it is doubtful your daughter will be able to shoot it as well as you can. Give her every advantage possible to make sure her hunt is a success. I sure wouldn't hesitate to rebarrel either.
I, too would get it crowned and float the barrel.
You May well know this but with M70's the stock screws should be ightened roughly as follows;
1. tighten front action screw very tight. Tighten the middle screw until the head just touches and tighen the back screw tight. Makes a big difference in accuracy with mine.
