[special-K]

If you want 100% original then rebuilt it. These trucks never drove badly when new. If you'd like to upgrade to newer design, the newer box will not really show as non-original except to an expert with their head stuck in your fender well or lying under your truck.

I have a funny situation where N.O.S. doesn't mean more valuable, at least to most. Years and years (decades) ago I had my GM dealer get me a new steering box for a '71 K/20 that had excessive slop. They listed for about $350-375 and I got a 30% discount, so still a couple hundred plus. I decided to part a Blazer I had so just used that steering box and left the new one on the shelf. Fast forward to about '07 and I discovered my '72 K2500 had wiggle at the sector shaft/pitman arm. I pull the N.O.S. box out, paint it, get the pitman arm I also bought back then, and OOPs! The parts guy had ordered me a 2wd box! I have my '67 project, but that sits on a completely rebuilt rolling chassis including steering box. With rebuilt units and upgrades readily available and the part not an appearance item I don't see it selling for even what retail was in the '80s. I'd be lucky to get what I paid at -30%. So I'm just hanging on to it for the future. My '67 project is performance oriented so I'll probably end up with a quicker steer box anyway.