Hi, my name is Mark Clapp and I live near Kansas City, Missouri U.S.A. I've been making plexi parts such as headlight covers and windows as an individual for about ten years now. The plastic I use will not crack so rocks/road debris are no problem. Also you do not need special drill bits for plastic such as required for acrylic. Any old bit will do fine with no cracking. I make pieces for many replica cars including the Karma GT. I've attached a few examples of the pieces I make. For light covers I usually ask $80 USD/pair and the shipping to the UK is covered with $30. I can make patterns and replacement parts from existing pieces even if they are cracked or scratched. Feel free to email me at:
mclapp5526@gmail.com
Thanks,
Mark Clapp