Yes, I use BUPA Global, just get in touch with them directly.
When I first took out my policy with them before they renamed from 'BUPA International' some 12 or 3 years ago I phoned them in the UK to arrange cover.
They also accept monthly payment by credit/debit card so you don't have to stump up the whole years worth of payment in one go and I don't believe they charge extra for that.