amp for ONKYO receiver

amc makes a perfecetly serviceable 2/3/4 bridgeable amp you can find on ebay for as little as $200--noce well made product

I once started out with a Harmon Kardon 85. I ended up getting two Hafler dh200's for the rears and centers. and a dh220 for the mains. Huge improvement. Cheap way to upgrade. Then for the heck of it I tried a Lexicon cp-3 in place of the HK. Now keep in mind the HK was about a $1000 piece. I put in the vintage Lexicon which can be had for a couple hundred. Night and day difference. The Lexicon blew the HK out of the water. BUT... That is when the bug bit. I ended up spending about $15,000 after that. So.. Be very careful.

I have three monoblock Sherbourn 1/300 amps. They'll do 200/8 ohm and 300/4 ohm. I have the 5 channel version and picked these up to upgrade down the road but don't need them anymore because I am just going to stick with 5.1 channel system. If you are interested I am happy to discuss pricing with you. I'll give you a great deal well under your budget.

There's a parasound 5125 posted today for $795. Come to a middle ground with the seller? The only other amp in the range that I see is a Rotel (I like the parasound better). You really won't find many 3 channel amps.
You could buy 3 monoblocks like Marantz. I wouldn't buy a stereo amp for R&L. You really should have the same across all 3 front speakers.

There are three amps that come to mind. I don't know the current prices. I have used Outlaw M200 amps from my Onkyo TX-SR805 driving all the 5 speakers. I upgraded the front left and right amps but continue to use the M200 (now the M2200) for the center and surrounds. Very reliable and affordable and excellent sound. I have also heard Emotiva amps and they are excellent. I have heard good things about ATI but haven't heard them. Good luck and have fun!