if you really are intent on raising it yourself, and I don't blame you, it's a wonderful experience, my first two were less than 24 hours old (cord still attached) when we raised them, mind you, I didn't know if I was raising field rats, moles or squirrels, turned out to be red squirrels, a tiny breed, anyways, your best bet would be to call a rescue to see if they have another "single" that you could raise with it, two are no trouble if you already are feeding one. we had no digital camera's back when I first started rehabbing, but here is a grainy pic of them 3 days after we found them. sorry about the bad quality.
notice the eyes are not opened and no fur, mother was moving them from the birthing nest to the nursery nest when she was killed by a neighbours cat, we found her a few days later.
this is the same two , 6 weeks later, living quite happily in my late iguana's cage, they had a huge tree branch to climb, a nest and the floor is heated.it was 6 feet high, 4 feet wide and 4 feet deep, you need a large space for them