Go for some headphones. This will be better than anything you put in that small room (I have the same space). Unless you spend some time with DSP or physical acoustic treatment. These headphones are what I should have bought and not wasted time with the 2-channel for my small office.
RAAL 1995 headphones, Magna and Immanis | Headphone Reviews and Discussion - Head-Fi.org
With your amp and preamp, the 1/2 the price RAAL SR1a phone would also be better than most things in that space.
If you insist on a 2-channel speaker I recommend the Magnepan LRS+. It was the best sounding speaker in my room. I am not saying it is the best quality speaker I have used in this room (far from it). However, I got the best sound from the LRS+. I even removed the acoustic panels that caught the first reflection when using the LRS+. Those panels were essential for all the other speakers I tried,
Now if you do not want to use phones and do not want to use acoustic treatment. Then another option, with any of the speakers mentioned in this thread is to talk with Mitch Barnett at this company.
Digital Room Calibration Services, Convolver, Headphone Filtersets (accuratesound.ca)
The dude will remotely setup your too big speakers in a small room and make it sound great (cost was $750). I think he only supports systems that have Convolution filters, such as ROON and JRIver. The guy is a digital genius.