You can use lattice to build the standards and a gate, and then weave climbing flowers (or fake vines) through. Here is a pic of the one we have at my barn but it doesn't have the vines through it yet, because it was new lol.
Void, those standards in the pictures you linked to are really pretty. We don't have a water tray jump at our barn. I wonder why. I can bet the rubber duckies would freak some of our horses out though. I also really like the picture of the lattice work jump. I knew you guys would have some good ideas!