Eh, at my shop we really don't reccomend remounting into the same holes, but if you really want to heli coils usually work fine.
If you want to remount the ski (which usually voids the warranty), then try to drill at least a cm away from the previous drill holes.
And fill the holes with plugs AND epoxy, just to make sure no water leaks into the core and rots your skis to death. I've heard of many morons not filling holes they fucked up on, and destroying their paying customers skis.