I change my own on the side of the road or even the campground.
I use a 12t shorty hyd Truckers Special bottle jack with a long handle that slides under the std round tube leaf spring axle next to the Ubolt. A few pumps lifts that end of the axle and not the whole side of the trailer.
The jack came with a axle tube adapter that fits over the end of the jack.
Or I can use a old 4500 lb rated HD 2 speed scissor jack with a long handle. It also just lifts one end of the axle enough to remove the flat and mount the spare. I keep this jack in my RV trailer along with a 4 way.