Adding fan to outside fridge compartment. Where to buy?

I like the "fan in the can" concept better. It will produce a strong laminar flow that can be directed at your cooling coils rather than create a general draft over the coils. You can make one yourself from a hollow cylinder with a muffin or computer fan inside, or you can use a bilge pump fan for boats, or Valtera sells one for refer cooling. I installed a old bilge pump fan at the bottom of mine blowing up at the coils but I only need to use it when the ambient temps get over 90 F.