I don't know if you can get a decent enough DAC at 200 bucks much less one designed for iPhone 5.
Here are my recommendations
http://www.ttvjaudio.com/Cypher_Labs_Algorythm_Solo_R_p/cyp0000003.htm
Wolfson DAC battery powered and designed with help from RedWineAudio.
Most docks that have digital output (like the Wadia iTransport, Onkyo S1 and the Cambridge Audio ID100) are designed for the older 30 pin dock connectors so you would need the Lightning to 30 pin adaptor to work. And these really benefit from an external DAC as well.
If you already have a DAC in your system, get either an AppleTV or Airport Express and play the music on the iPhone via Airplay, hooking the optical output from the AppleTV/Airport to the DAC's optical input.
Here are my recommendations
http://www.ttvjaudio.com/Cypher_Labs_Algorythm_Solo_R_p/cyp0000003.htm
Wolfson DAC battery powered and designed with help from RedWineAudio.
Most docks that have digital output (like the Wadia iTransport, Onkyo S1 and the Cambridge Audio ID100) are designed for the older 30 pin dock connectors so you would need the Lightning to 30 pin adaptor to work. And these really benefit from an external DAC as well.
If you already have a DAC in your system, get either an AppleTV or Airport Express and play the music on the iPhone via Airplay, hooking the optical output from the AppleTV/Airport to the DAC's optical input.