Anytime you add birds you will have to deal with the establishment of the pecking order. If you get some new birds I would try to keep them separate for a few weeks to make sure they are healthy, then introduce them, as long as the birds are all close in size. Many posts you can look up about it. As far as the birds go, I saw a Craigslist posting in central jersey for young BR, RIR and a few others. They were located in colts neck. Let us know what you do. Dont beat yourself up over it, it's an accident and if anything you will be better prepared for when they are out.