German retailer Media Markt has listed both the Lumia 820 and Lumia 920 on its website with release dates of November 1st. Both Windows Phones are expected to be made available on that day, should the reported date hold true, and will be priced at €449 (approx. £360) and €649 (approx. £520) respectively.
Update: It seems Media Markt has bumped the date from November 1st to November 15th. This change has occured the same day a German Vodafone store stated on its Facebook page that they will be stocking the Lumia Windows Phone 8 handsets at the start of November. We'll have to see if the date sticks. Thanks, Schneppe, for spotting the alteration!