Smaller Dunlavy (SC-IV or smaller) or Duntech (Princess or smaller) speakers will work OK as you mention, you'll lose a little depth and might get a bit more bass than otherwise specified in the measurements but otherwise you can be OK. The best close to wall speakers I have ever heard are the Snell Type A-IIIs, designed to be placed up against the wall and terrific speakers. I think there's a used pair up for sale on the 'gon now. Particularly good with classical music, and good bass extension. Only problem is that they're no longer in production, don't know about how well they can be serviced/repaired.
