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For a small area (mushroom tank) I have plugged a Mini Humidifier into a Humidity Controller. It's a little awkward because the humidifier has a toggle on/off button, but I found that if I rubber-band it into the pressed position, it works.
I 3d printed the plastic cone. If you don't have a 3d Printer I would really recommend getting one, it's really useful for this hobby. If you aren't going to get one you could try using one of the ready made "humidifier sticks" likes this one or many others found on amazon. I used the wick sticks that come as replacement parts for that product but I am going to switch to wicking rope so I can move water farther from the reservoir.
You can buy the disks and the pcb circuit board that drives the disk on amazon here. There's tons of disk replacements and other sellers, but you have to make sure you get the kind of disk that is perforated, there's another kind that is just solid and meant to be submerged in water.
If you want to make your own PCB so you can customize it to suit your needs you can follow this video. If you have experience or are willing to learn you can use EasyEDA to design your own pcb and JLCPCB to have the pcb manufactured cheaply in small batches of 5 and shipped to you.
Hope that helps! I'm on here pretty often if you have any more questions. I love tinkering with stuff so just let me know. I could always 3d print you some small parts if you need as long as you are willing to pay for the material and shipping.