I am currently powering my Klipsch Heresy's with a vintage Marantz 2252B receiver and a B&K ST2140 amp. IMO, total bliss. The 2252B alone does a wonderful job with the Heresy's in my 13 x 13 room. I have used it to power Fortes and Quartets with the same results. Mid power to high power Marantz vintage receivers(2250, 2252B, 2265B, 2270, 2285, 2325, etc.) will all be fine choices to complete your quest.
http://www.audiogon.com/cgi-bin/cls.pl?miscrcvr&1303844462&/Marantz-Model-2252B-
80's, 90's, 2000's Denon integrated amps are also good choices to stay within your budget.
http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1305321029&/Denon-PMA-2000R-Integrated-Amp
NAD integrated amps also.
Bill
http://www.audiogon.com/cgi-bin/cls.pl?miscrcvr&1303844462&/Marantz-Model-2252B-
80's, 90's, 2000's Denon integrated amps are also good choices to stay within your budget.
http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1305321029&/Denon-PMA-2000R-Integrated-Amp
NAD integrated amps also.
Bill