Rear Axle Pt. 1 - A Dilemma

Where to start, where to start? 

I can't afford a beautiful galvanized chassis. Well, I can, but not at the usurious rates that pass for shipping these days. I asked Richards what it'd cost to send me one and, get this, it's 80% of the cost of their product. I was expecting it to be expensive, but not *that* expensive. I'm not spending $9,000 on a chassis.  [Editor's note: I did, in fact end up spending more than that on a chassis. :( ]

So in the meantime, while I figure out what to do, I'm tinkering with the axles. 

I have two axles. One came with the truck, and another I've purchased. Both are... not great. 

The original one on Duffy, at the left above, looks to be mostly OK. Not totally rusty, like the one on the right. It's in pretty rough shape. There are a few points of concern, though, on the original axle that I'm not sure about.

First, there are these lovely dents that correspond nicely with some chunks that came out of the crown wheel. Those made an audible clunk in the pan when I drained the diff. Yay!

Then, there are these really deep furrows in the axle casing from wear from the u-bolts. Where could those have come from, you ask? Well, we might have gotten a clue here:

... where the diff has clearly been hitting some, uh, rocks. This truck led a properly hard life. And here:

... yeah, I'm not sure the leaf spring pin holes are supposed to be that, uh, elongated. Finally, and it's hard to see this, but the brackets for the bottom of the shock mounting bolts are quite dented, as well. They're not flat, as they are on the rusty other axle case.

Both axles have seen better days. My first question to ask is: is it worth cleaning and repairing either axle casing? I can get the leaf spring pin holes welded up easily enough, but those furrows in the axle casing are a bit worrying. What if the metal is really thin and / or contacts the axle? 

Does the condition of the shock mounts really matter? If they're bent, how will that affect the shock?