Thanks for all the ideas, I'm hoping to get some half tint rear lenses so if I get um I'll make sure they're well sealed when I fit um 
Nah dont bother doing that, just half tint the ones you have, is easy to do and costs about £12 in total

. If you cant get the old ones to seal though it might be worthwhile.
Silicone can be bought at B & Q etc for about £5 and be used on loads of other bits too
