Best Buy: Apple MacBook Pro 13.3" Intel Core i5 4GB RAM 320GB Hard Drive (MC700LL/A) Early 2011 (Certified Refurbished) Silver A1278
2011 Macbook Pro 13" A1278 RAM Upgrade - YouTube
MacBook Air (13-inch, Mid 2011) - Technical Specifications
Amazon.com: Apple MacBook Pro 13 inches MC700LL/A (4GB RAM, 320GB HD, macOS 10.13) - 1 Pack (Renewed) : Electronics
Apple MacBook Pro 13" 2011 i7-2620M 2.7GHz 8GB RAM 500GB HDD PC1226901 | eBay
A-Tech 16GB (2x8GB) RAM for Apple MacBook Pro (Early/Late 2011), iMac (Mid 2010 27 inch 4-Core, Mid 2011 21.5/27 inch), Mac Mini (Mid 2011) | DDR3 1333MHz PC3-10600 204-Pin SODIMM Memory Upgrade Kit at Amazon.com
Upgrading the Late 2011 MacBook Pro to 16 GB of RAM! - YouTube
Apple Macbook Pro 13 inch Early 2011 2.3 GHz Intel Core i5 16GB RAM 500GB SSD | eBay
MacBook Pro 13" Unibody 2.4GHz Core i5 Logic Board
Apple MacBook Pro 13" (2011) Intel i5 2.4GHz✓4GB RAM✓128GB✓MD313LL/A -- *NO A/C* | eBay
Apple MacBook Pro A1278 13" 2011 Core i5 3210M 2.30GHz 4GB RAM 500GB HDD Read. | eBay
Apple MacBook Pro (13-inch, Early 2011) 2.3GHz Intel Core i5, 6GB RAM, 128GB SSD | eBay