I know someone that has a bed like the one I've linked and always liked it. Now though, I looked at the links you posted and there is a big price difference between them all.
Seems like there was a YT member that made beds similar to the one PVC pipe bed. I don't remember who it was, sorry.
Riviera Outdoor Pet Chaise - CatsPlay.com - Fun furniture, condos and climbing gyms for cats and kittens.