One of the big Musical Fidelity integrated amps will do the trick. Maybe a M6si. But I have to say that would not be the way I would go. You can only get so much out of a little bookshelf loudspeaker. You really want the power and weight of a good floor stander as your next upgrade. Maybe a loudspeaker that matches your PrimaLuna a little better.
Amp & Pre or Integrated for Dynaudio Heritage Special
Currently have a PrimaLuna EVO300 integrated and looking for something that would do these speakers justice. Would probably prefer to go the integrated route but not opposed to separates. The Dyns are extremely fast and somewhat forward. Don't want to lose the PRAT which I love but need a sweet top end with good power.