I got a used restaurant ventilation hood from a guy who installs restaurant hoods. He had one hanging around in his backlot. I bought a "squirrel fan" from Granger. They helped me pick one out. It is loud, and you have to have a Tax id/ business to buy from them but my husbands friend had one.
I tried to put the picture of it when it was being installed but it is too big. This is the pic on Facebook