The Heresys are very efficient, but very forward speakers. Unless you're doing DJ work with them you'll only need a few watts (20 would be plenty, 2 could be enough). I'd look for something known for a softer/recessed treble. Tube amplification naturally comes to mind.
I'd look for a used Scott tube receiver. Mapleshaderecords.com has refurbed ones, but the price is $1500 - 1800. Note that the integrated amp version goes for about half. You could add Sirius, Squeezebox, or just do internet audio streaming for a lot less than FM and get much better better sound.