Good news for all existing RadioKit SDK license holders: the current version of the RadioKit SDK works fine with iOS 7 as-is, so unless you want to make other iOS 7-related changes due to other features of your app, your existing apps should continue to work just fine.
For anyone just getting started with RadioKit, I have put together a simple iOS 7 / Xcode 5 demo project which can be found here: An XCode 5 (iOS 7) utility app - http://www.stormyprods.com/Demos/ios7/RadioKitDemo.zip
If you just want to grab the most up-to-date RadioKit SDK (version 2.6.2), you can get it here: http://www.stormyprods.com/Libs/RadioKitLib-XCode4.5.zip