a friend asked me where does he get old bike parts, he's got an old Triumph, "28 wheels I think, pedal brake, he needs a new rear hub as his brakes are worn out and he can't get parts this old, bikes probably 60 or so years old, he said something about the brakes having porcelain on them and it's worn. I don't know where to look, is there a website or something that would have these parts? thanks for your help