I raised hoistien calves when I was a kid about 20 years ago. I raised about 20 to 25 head at a time bucket feeding them from babies. I got them from local dairies that had cows that calved and didn't want to go through the trouble of raising them. At that time I paid $25 per head and would get these calves at one to two days old. Some did not even there mothers milk which is important. As a result I would lose one ever now and then. It was a great experance for a young kid. It tought me alot of responcabilty becasue the calves has to be feed before and after school. Each feeding for 25 head would take me about 2 1/2 hours. GOOD LUCK!
P.S. You can also get young calves to feed from feed lots, but they may not all be hoistiens.