They do indeed ship from the UK, items usually come next day for me, two days at most.
When an item says 'usually delivered in 7-10 days', it means that they need to ship a copy over, if it says in stock then they have the item in their UK warehouse ready to post.
They do charge in dollars. My last order came to $190.18, which according to xe.com today is £120.13.
In my bank account the charge shows as £119.53, so it may vary depending on the exchange rate when you place an order, and when you are actually charged.