A cheap pizza toaster! Why am I telling you this? Because it’s not for food, of course.
I intend to use this for finish curing. It has the right temperature range, and is inexpensive enough that if things don’t work out it’s no big deal. My first experiment will be with some spray enamel that cures at 200 degrees Fahrenheit for two hours.
I have a pink anodized case I’ll be refinishing with white engine enamel - could be a disaster, could save me fifty bucks vs powder coating. Either way, I’ll show you what happens. 
Edit:
Yay, it works.
To be clear - I’m testing this in my kitchen, but will be curing the enamel outside.