I have an Alpine MRV-F345 laying around that can be run in 3Ch mode. I have the original box and birth sheet (104w a channel), but only thing I'm missing is the top cover for the display and controls. I removed it because I thought it looked better without it but lost the screws. PM me if interested...I think it can do 104x2 + 350ish @ 2ohms. Not 100% sure on those ratings though...we could find out more by calling Alpine. You'd be better off with a set of components up front though.
I actually have the top cover btw, just no screws for it. They are tiny and have an allen head...