Springbok10: Forget any technical limitations - just tell me of any high quality floor-stander that is designed to be close to the rear wall, please!
Look for front-ported speakers. Besides looking for a model that was designed with a front-port, if you deal with a small quality company (Tyler is one but there are others too) they can actually tweak a model to your needs. Another one who can accommodate such needs (and is known for beautiful cabinet work in addition) is Salk. Give them a call or email, explain your needs, and see what they can offer.