MobilePros1 via eBay offers the refurbished Unlocked Apple iPhone 5 64GB GSM Smartphone in Black, model no. MD662X/A, or White, model no. MD643C/A, for $299.99 with free shipping. That's $130 under our September mention of a refurb and the lowest total price we've seen for an unlocked 64GB iPhone 5. (It's also $150 under the best price we could find for a new one.)
Note: No warranty information is provided.