Hey,
You have to audition the amp with the R7s regardless of the brand. That being said. I would try any of the Hegel line. In fact they have a new integrated amp coming out called the 600. I am sure it is awesome. That being said, the old Hegel 590 should be a really good deal. Any of the Hegel line can push those speakers due to the damping factor. Look at past audio show videos. Kef and Hegel are paired together a lot. Just an option. I hope this helped.