My nearside Xenon headlamp needed adjusting and whilst at the garage the mechanic attempted to realign the unit, at which point one of the white plastic cogs which adjust the unit for Up /Down Left/Right broke!

I am now told that these little cogs costing pence to make are not a order-able part so I need a new Headlamp at £600! Surely this can't be right? I need a whole new headlight for a small white plastic cog?

Any help suggestions or pointers would be much appreciated as I daren't attempt to adjust the offside just in case that breaks too!