Easiest way: Get a good, big cooler; fill with hot tap water (mine is 130°); add hot water from kettle to bring up to desired temp. (Use a Thermapen); drop in vac-sealed packs of food to be cooked; after 30 min., add more water from kettle to bring temp. back to target temp. as cold food will have cooled the water a few degrees; check after one hour and add as necessary. After the first 90 min. the water temp. will drop very little if the cooler is a good one. I have gone overnight with as little as 6° drop in temp. I cooked 120 golf ball sized meatballs in one 38 qt. cooler using this method. Froze them in the same vac-packs and smoked them "raised direct" (after wrapping in bacon) for MOINKs at the Ozark Mountain Eggfest last year.
I have a Sous Vide Supreme but it would hold only 1/4 this amount.