Exactly how high is the opening for the centre? The
KEF Q350 is available in matte black, is 8 5/16" wide and is $800 a pair on Crutchfield. The
Q650c centre speaker is also $800 so I think that fits your budget. Since it uses a concentric speaker you do not have to worry about off axis response. Only issue is that it's 8 7/16" high, but with rubber feet. The KEF website says that it is 214mm with the feet and 210mm without (210H x 629W x 304D in mm). KEF Q series is known to have pretty decent dialogue for home theatre and may be available in your area for auditioning. They make smaller speaker which you could use for surrounds later.