Hi Alex, welcome to BYC!
I like My Pet Chicken. This is where I got my chicks from and they do ship small orders. My RIR are friendly and healthy. You can also look for a feed store near you, RIR are pretty common to be found there and we are just about at chick season!
Be careful with the purchased, ready made coops. A lot of them (most of them) say they are for 3-4 hens but really they are only suited to two! Especially a bigger bodied hen like a Rhode Island. If you want 4-5 chickens buy a coop that says it's for 8-10.