I think I could probably do the wood axle
Wood axle boxes aren't that difficult. This is is how I made mine.
I cut a groove in a piece of 1½" square oak on a table saw. No dado. I just set the depth, started in the center and moved the fence over slightly, making a cut on each side, until the groove was the right width.
The groove fits a ½" stainless steel threaded rod, it's snug but not tight and the rod will slide in & out. The groove is capped with a piece of ¼" x 1½" oak, clamped and glued. A few passes with some fine sandpaper on a block to clean up the glue joint and it's ready to cut to finished length.
The plastic/rubber wheels were for setup and assembly. When it came time for wood wheels, I cheated. I bought mine online.