You're talking about the wire baskets? Try eBay first of course, but there's nothing very clever aboiut the locking mechanism, as I recall. They could be taken off with an Allen key, if it weren't for that little nub in the middle there. If they're on tightly, I would advise you to centre punch that little sucker then drill that nub out of the way, then use an Allen key. Of course, they will then be less secure in the future - the baskets that is - but making a tool to fit would be a nuisance and I suspect your chances of finding a "key" out there are slim. If they're not done up tight, I would think a couple of flat blade screwdrivers might do.... Last idea - get an Allen key of the right size (measure the flats in the basket - accurately) then have your friendly lathe operator open the end for you....