I have a mid-80's Sharp (non-carousel) "Half-Pint" that runs at 400 watts. The size is about 13" x 12 x 13"". The next version w/ carousel requires 600 watts. 
They are usually $20-$100 on ebay or craigslist.
Although I intended on using it on camping trips, I've never taken it along. It just sits on my garage shelf.� For the space it takes up, just doesn't seem worth the effort. I imagine I could leave the camp pop-corn popper at home.
Chris 3
Wisc.�