Most Borg outposts have them, but you might want to spring for the Type 3R Raintight - they have a flange around the door to keep drips out and with some stick on foam gasket turns it to Darn Near Bombproof. Rainproof only has knockouts on the bottom, and certain models have no pre-punched holes, the rest (sides top front back) you have to drill or punch
They are in generic form from many makers - Circle AW, Hoffman, Wiegmann, etc - that keeps them cheap. Pick a size, 6X6, 8X8, 12X12, 16X16 and several rectangular sizes too 9X12, 12X18 And pick a depth (4" 6" 8" 10") to fit your VFD or devices you want inside in most formats If you want really long and skinny that's a Gutter - 4X4X24"
If you want a cooling fan like that be sure to put it on the bottom or put a shroud over the inlet to keep the larger chunks from being sucked in. And punch in a screened hole or two to let the hot air out