Can you get just the glass? For what they cost and the likely quality of a second hand one I'd buy a new unit - They have them at GSF for £11.40 and as it would be new the plastic surround won't be cracked and degraded allowing the glass to drop out again.
Surely for the cost of a new full unit its not worth the trouble ! But if you must, go to any local glass cutting shop and they will gladly cut you a bit of mirror glass (used for shaving mirrors) and you can glue it in- cheap and simple , just like me.
Thanks Davidoft, I bought a cheaper pair of mirrors and its the drivers side that's fallen out. Just wondered if anyone had one so I could refit the original mirrors, I think they look better anyway
Lardy. Are you still looking? I have a complete mirror with the mirror glass stuck over. Whether you could soak it to unstick it. The mirror base itself is no good as the bottom thread on the arm has snapped. Yours if you want to try.