Moving newborns?

Check for milk bands in the bellies. That's a good way to tell.

Yes, you're fine in moving babies early. The good thing to do is wash the mother too so that she doesn't smell like her babies. Mice are good mothers, they will take care of theirs and other mice's babies.
If worse comes to worse and you ever need to ween the babies off of the mother for health reasons you can always attatch the pinks to a rat mother. Rat's are smart, they will nurse mice until they are weaned... but after that they will kill them if not quickly removed.