I would go with the thought that all dealers are open to reasonable offers.
There is no harm in asking but remember that they need to make a profit in most cases!
Just a reminder that the OnlineCoins Auctions will end in just over 2 hours (new ones to begin thereafter)
(Also got some Auctions running on eBay - they began yesterday and will last 7 days unless I get a few more BINs!! )