The Charney Audio Companion with the Omega RS7 driver would be a great way to go for your room size. I have listened to them in a 14x19x9 room and the bass is sufficient. You can always add one down the road if desired. Your choice of the LM 518a is far and away enough power. The RS7 driver lends itself well to low watt SET amps as well as SS amplification. I have a pair and listen in my 11x15x8 room. I currently us a pair of ANK interstage mono's, but recently demoed the Digital Amplifier Company Stereo Maraschino (STM) integrated. It gave my 300b a serious run for the money and is less than a quarter of the cost. A very good integrated I could easily live with had I not owned the ANK monos.
Enjoy your journey.
http://charneyaudio.com/
http://www.cherryamp.com/
Enjoy your journey.
http://charneyaudio.com/
http://www.cherryamp.com/