Dave, your axle looks fine to me judging from the ground clearance of you trailer.
My axle was completely dead. I had about 5 inches of ground clearance.
Going down a flat road everything bounced out of the cabinets.
I replaced the axel under my 1988 Lil Bigfoot
a couple months ago.
There are no stock axles built today that will fit due to the A frame configuration of the axle.
The frame has to be modified.
The axle shop that did mine modified the frame forward of the original axle and installed a trailing axle.
I had prices from $580.00 to $1100.00 so it pays to shop around.
I told them what I wanted, with no advice on my part, and let the expert find the axle and do the job.
It worked out well.