Your trailer is equipped with the Torflex style axle.(torsion).
The D80 style is what most other's are equipped with.
Unless your planning on some serious off road traveling modifying the AS axle to gain height isn't very practical.
If you look at the diagrams in the PDF you can get a better idea of how different the two styles are. The torsion, (AS) style would require much more fabrication for the mounts/brackets.
Now look at the leaf spring diagrams, notice how much easier it would be by just increasing the distance between the leaf spring and axle tube.
Lets get you LEVEL first, I think we can keep your "tail" off the road.
"Sticks & stones can break your bones...and hail will dent your Airstream"
So when is this..."old enough to know better" supposed to kick in?