Oh, I hope your baby is ok. Seems to be doing fine now.
I use these scales for shipping, like Sunni said. They seem to be extremely accurate, weight to the tenths of ounces.
This one weighs up to 10 pounds
Amazon.com: USPS PS-100 10 lb. Desk Top Postal...
This one weighs up to 5 pounds
Amazon.com: USPS PS-105 5 lb. Desk Top Postal...
You can possibly find it cheaper on ebay.