I use an Audio Aero Prima MKII tube hybrid integrated amp. New I think it was around $2000 maybe a bit more but from time to time I've seen one on audiogon going around your budget. I love the sound of this amp, it's based on a mini tube and a mosfet amp, very sweet sound. You could also check for a used Red Wine Audio Signature 30, now that the 30.2 has been announced, there are some used for sale around your budget. Your A/V-3 definitely deserve a better amp than a Yamaha HT receiver, you will have quite an improvement with a good stereo integrated amp.