Best of the best would be at least one other chick. I have a solo chick right now, 1 week old today. He has a stuffed monkey for snuggling with and I go in and talk to him/hold him a lot. I have eggs hatching Nov. 11th and they will join him once they are steady on their feet. I tried to find more chicks but it didn't happen. He listens to TV/radio during the day also, but I let natural daylight be the control.
He is a bit spoiled, because I feel sorry for the little guy. He's a bantam Columbian Cochin. The worst I can imagine is that he's going to be bonded to humans more than to other chickens. Luckily, the soon to be hatched can help with that.
Here's the brooder setup for just him - I'll go bigger once the others hatch. He between the monkey's arm and leg.
And here he is at 1 day old.
Check your local Craig's List for chicks his age, try all you chicken buddies, too. I couldn't find any, but a feather duster or a stuffed animal comforts them. And the radio/TV gets them used to outside sounds coming in, plus frequent visits with humans.
Introducing one chicken to a flock is very difficult. Time and patience. Wait until the chick is as big as the adults, perhaps separating by a fence or in a cage for a couple weeks first.
ETA, I did call My Pet Chicken for some more chicks but they are winding down on hatching for this year and couldn't ship until the others would be hatching. They do have some available to ship on Nov. 8th, and I can honestly say that I have never had such good customer service on the phone like I did with them!