OnSale-eCost via eBay offers the HP 8GB DDR3L-1600 SODIMM Laptop Memory, model no. H6Y77UT#ABA, for $62.99. This $10 mail-in rebate cuts that to $52.99. (MacMall has it for the same price with this $10 mail-in rebate.) With free shipping, that's the lowest total price we could find by $23. This 204-pin SoDIMM is low-voltage and features memory speeds of 1600Mhz.