In reply to mypyrex: Yep - there are gems around like that. Popped into Harry Halls because asking for a bolt to replace the one that broke on my pannier. They just gave me one.
I believe the ever legendary Chris Tan bought a Karrimor rucksack from a car boot sale with a few bits missing so rang up to try and get said missing items. After a brief conversation it turned out that the bag he had was one of the few missing from their museum collection and they offered to exchange it for any bag in the latest range he liked.