A multich receiver is a better bet generally than a two channel if you're running multiple speakers due potential for impedance issues; a receiver might do okay depending on the speaker specifics and listening levels. Going to the used market would be what I'd do, usually a good choice of older avrs (audio video receivers) with multiple channels of amps since you don't need much on the video side and sounds like your audio needs might be minimal....what would be the source of music?