Thanks for the responses, "suitable for Caravans".....I completely missed that so thanks for that. I knew they were used in campers in Europe but I forgot they called them caravans so I wasnt getting hits on Google (smacks forehead). I couldnt find a picture of the one I am looking at but its a small square about the size of an old 1950s B4 Toastmaster toaster and can be mounted on a bulkhead.
Toyo stoves are great but would be overkill for our small TT. I retired out of the Army from Ft Rich and we heated our small 2 story house with a Toyo...filled a 300 gal oil tank about every 9 months or so which was great and the only supplemental heat we used was some electric baseboards in the bathrooms. We bought a small 14 foot TT because it is all we need, its easy to tow and camp in, and for us, when we use the Alaska Marine Highway you get charged by height and length so.....
The metering valve...well its really just a needle valve where you adjust the fuel flow manually and so it is hard to adjust the heat. A stove like this would only be good and used if its pretty cold out or to warm up the rig in the mornings as they tend to be hard to regulate heat wise and they will drive you out.
As for the walled tent and wood stove; we are of an age and have some physical impairments that make that less appealing. We are still adventurous but as much as I like to think I am as ready to go today as I was 20 years ago I have to be realistic. And another factor for us, we really, really, really like bringing a bathroom with us. I never thought that would be a big deal but man that alone makes me wonder why we tent camped all those years!
We are also looking at some sort of wind generation to charge the batteries like they use on sail boats. I am kind of playing around with building some sort of portable mast that would fit into one of the stake pockets on the truck to mount a small wind generator on when we are camped.
And finally, waste oil heaters. I love the idea and will check it out. I even like that idea for heating my pole barn shop since we generate a lot of waste oil with the farm machinery. Thanks for that idea.