No personal experience with them (and website is down at the moment), but you might try:
QuickSilver Exhaust Systems
7 Towergate Business Centre, Coopers Place, Wormley, Surrey GU8 5SZ, UK
T: +44 (0)1428 687722 F: +44 (0)1428 687790
info@quicksilverexhausts.com
www.quicksilverexhausts.com
Here's why:
http://www.mangustainternational.com/technical_detail.php?id=36
I hope that helps. Will you show us some pictures of your nice car please?
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