Sorry Guys wasn't sure where to post this but it might be of interest....... I have just head my o/s Headlamp crscked by a stone thrown up and instead of replacing it I am repairing the crack with "Halfords" Winscreen glass repair kit...
Another trickI have learnt is to use Super glue.(as its clear) Most pound shops sell it for well, a pound.
Rub the ofending crack with sand paper (gently) as it gives the glue something to key to. Lightly dribble glue down the crack and wait for it to set. Repeat dribble and hey presto repaired light. Much cheaper than a new unit.