Can’t find a Tripod Stabilizer for King Pin “Ball”

Bought my 5th wheel pin stabilizer in 1985 for our 1st rv trailer. It works great for what it does which is stabilize the front of the trailer.
Common sense/experience tells us it does nothing for the trailers rear so some type of stabilizer at the the rear is needed.

JTs or a similar product does the same thing for any type trailer that wiggle or motion isn't desirable.