In reply to Nick Gough: always been happy with mine and as much as they are heavyish it means they go in easier than a lot of the whacking you have to do with lighter picks, they're bomber and the head bolt system is great IMO. you'll need to change the leashes though as the simond ones are rubbish. they were the tool of choice for many years alongside quarks.
ye can't get replacement picks though. someone else may know of a source.