Can you use your ipad to stream to an Apple Airport Express? Another possibility is the first generation Apple TV which has component video output. Unfortunately Gen2 and Gen3 (current) Apple TV have HDMI output only.
I believe the Roku boxes (under $100) have Tunein Radio and an ipad app. Hopefully the ipad app would allow you to control the box. They have either RCA out or min a/v jack outputs depending upon the model.
Then there is the Onkyo TX-8050 2 channel receiver which has built in network capability. Denon makes a similar unit in their mini line.
Many of the latest generation AVRs from Denon, Yamaha, Onkyo, Pioneer, HK, etc. have ipad control and internet radio features.
Lastly there are pricier Network Audio players from Marantz, Cambridge Audio and others. I believe these have internet radio capabilities as well.