Hang around the plant construction dump. Original suggestion was to make a water tight, humidity dry enclosure with electric drying, a simple resistor using 120 vac. Also places for good ground to shield. Paint the outside to match the house.
Done all the time commercially. You don't want foam or plastic cases cracking in wx extremes, etc. critters including wasps burrowing in every nook and cranny.
Otherwise build a respectable little wooden, side mounted enclosure complete with adequate ventilation, shingles on its little roof and with nice door for inspection, frequent cleaning, nest and mud wasp removal.
. Seriously, Nothing wrong with that amd that's why I mentioned k4kyv's at the base of his commercial vertical.
Think about it, the necessary seals, feed-throughs and for G's sake don't build one in an all foam cooler. Hey, for max cachet, find a period , double walled, interior galvanized Coca Cola cooler. --Would go with the Mail Pouch sign on the barn. Neighbors would ooh and ahh over your Cool Tuna.
