I found something for the "carry it out toilet" for the 
moments.
I know you weren't asking about a pooper but I saw something cheap that looked like it would work really well. It was a folding metal card table chair with a big hole cut in the seat. Then it had a toilet seat bolted to it. He just used a trash bag with a little water in it and put it in the hole in the seat. the weight of the toilet seat held it in place.
Wait, I think I have a pic.
I was tempted to ask If I could use it.
