Also second the notion of something Double Eagle flavoured with the Falcon Fire mosfet, they're class and pretty much unbeatable for the money unless you fancy fucking around and tinkering. My mate bought a M904E around two and a half years ago when we first started playing and it's sat as old reliable the entire time, never missed a beat and even survived me when I had no idea what I was doing (because turns out, buying epic upgraded G36s off used airsoft doesn't mean it'll work or be any good).
If you think he'd fancy something a little more SMG shaped, the UTR-45 is another solid choice by Double Eagle and pretty much has the same internals, although the mags can be a little bothersome with regards to carrying as they're UMP flavoured and come with the quirks as such.