I did not know mini fog machines were a thing until now - and now I want one! Do you have any references? I think apart from the see-through portion and some fan the windtunnel would be quite 3d-printable.
The professional grade units in Norman's video are $150 and $250, but there are plenty of listings around the $50 mark.
They are basically just vapes with a small fan. IIRC, the special smoke fluid is just the vegetable glycerin base typically used in vape products.