I've bought through here (offshore) in the UK: http://guernseymint.com/
Pretty happy with the service, although they are slow answering email (if they ever do). They are an old established business (going back 100 years I believe). They will store your metals for free for a year (although we are always told never to do that - in case they go bust!). GM will also ship to a separate third-party secure storage company on Guernsey for you, if you don't take delivery yourself. Storage and Lloyds insurance there is about 1%.
By buying and storing in Guernsey - UK folks avoid the (almost criminal) 20% UK tax on Silver.
Anyone else using Guernsey Mint? / experiences?