It's about a 30 minute drive from my favorite feed store where I've picked up all but four of my chicks at various times.
YES, dress in layers so you can get down to a light shirt for the ride home with the heat cranked up.
I'm afraid I just drove home with two chicks in the paper bag the feed store employee put 'em into, twice. When I had more than 2 chicks, they'd give me a small box.
They always settled down and stopped peeping to sleep as soon as they got warm. Well, except for the railroad crossing ... that woke 'em up. And then the dash from the car to the bathroom nursery and into the brooder.....
Get yourself a couple extra chicks. Just in case. Seven chicks won't be any harder to raise than five, should they all survive (and they probably will.... it's just that sometimes new chicks "fail to thrive" and don't make it). Bet somebody in your family will adore the two extras, too.
I recommend any sex-link, black or gold as safe bets, or a Black Australorp, or Silver Laced Wyandotte, if they are available.