Rocket toaster oven?

I've finally come to the realization that I don't often need to cook 6 pizzas at one time...  Has anyone made a scaled down rocket oven that might be considered "toaster oven" or "microwave" sized?  

To be perfectly honest, I rarely am organized enough to be cooking more than one pizza at a time.  

(I only have one big wooden pizza loading spatula thingy, although I do have a big metal pizza removing thingy, so sometimes I manage to cook two pizzas at a time.)

Thanks Julia, I realize one can use the standard rocket oven to cook a small dish.  But it seems like if you never need a big oven, might we be able to come up with something smaller that still works?  Maybe the next kickstarter :)

I've often thought about this. One simple approach would be to combine a Dakota fire hole with a small cobb oven.

I also have a 6" cottage rocket I made at an Uncle Mud workshop. The top of the 19" wide barrel is of course removable so I've contemplated building a mini version of Paul's barrel oven for it.

In the meantime, I've been using Biolite's Basecamp Stove (basically an electric-assisted rocket stove that uses the resultant heat to recharge a battery to use for the next firing) with the same company's pizza oven attachment to make single pizzas and such. Sadly, Biolite has moved on from those items and no longer produces them. I could make a single pizza with nothing more than six nine-inch long sticks of wood as thick as my thumb; three to heat the oven to 400 degrees and three more to keep it hot for ten minutes to cook the pizza. A cooked pizza from six sticks of wood; it seemed like magic.

With that option gone, I've been experimenting with a "Pizzacraft PC0601 Pizzeria Pronto Stovetop Pizza Oven" on top of a "TAFEIDA Upgraded Camping Rocket Stove."  Not very stable so I need to make some modifications to it.

How about using a TLUD or soup can gasifier to provide a relatively low steady heat over time?
Even a simple bucket rocket stove would be plenty, and building a fan assisted rocket stove ,  would not be difficult and would allow a smaller sized stove to be viable.
I have some tables I've built from commercial sized aluminum sheet pans that would be ideal for  supporting a small  woodfired oven.
I would want to mount the stove underneath, with a way to raise and lower them, or a way to bypass/ deflect some of the exhaust.
A stainless steel hotel pan or a sink could be the inner part of the oven, cob or insulating cement the outer skin.

I was thinking of using a stainless ShopVac hull as the oven chamber, inside of an un-split 55 gal barrel outer shell. (I've saved a few up over the years at the transfer station...)
Haven't done the exact measurements to see if there's the right clearances... but it would be a slight scaling down at least, even if it still had insulation on the outside.

Our countertop Breville oven takes 1/4 sheet pans or a standard frozen pizza (14"?) which seems like a good "small oven" size. It's also tall enough to roast a chicken (without spatchcocking).
Maybe a 5 gallon metal paint can would work for the oven chamber?

A lot of the commercial patio wood-fired pizza oven thingys are flatter, flying saucer shaped. More closely shaped/sized for pizzas. (go figure)
Maybe a cut-down in height drum would work?

Seems like a white oven chamber in a bell, and a j-tube is the basics, no?
Then, it's find a ready-made chamber, or fabricate one.

Not quite a rocket oven, but perhaps an "Aladdin Oven" might be a good starting point.  About 100 years ago someone worked out a way of using a common Aladdin oil lamp as a heat source for cooking in a small oven.  I first read about it in the Mother Earth article listed below.  The second reference is a really neat little booklet from 1901 that discusses building and using an Aladdin oven.  You can download a free copy from the site.  A modern version might use a TLUD burner as suggested earlier by William Bronson.  The attached (I hope) is image is from the booklet.

https://www.motherearthnews.com/diy/aladdin-oven-zmaz74ndzwar/

https://archive.org/details/howtomakeusealad00atki/mode/2up

I'm not sure if smaller steel drums are standardized at all but one website I looked at had 10 gallon drums at 14.3" diameter x 18.6" long and 20 gallon drums at 18.7" dia x 21.5" long.  The length difference isn't enough for the exhaust chamber and chimney but the smaller drum could be shortened to 15" to be roughly square.  Then there's be room for a 6" chimney.  Or smaller since it's a small oven.  And the diameter difference feels about right.

Using standard drums/supplies would be awfully nice.  As would not having to split a drum...

If I were to go for a j tube, I think I would use the tank from a 40 gallon water heater and make an Uncle Mud style  rocket like Timothy mentioned.
The oven could be inset into what is usually thermal mass,it could be an insulated dome that sits on top of the cylinder, or it could be made from nesting stock pots.

Another handy shell for such a oven is a 4 or 5 drawer filing cabinet.