Well, I just found a manual steering box for my 1973 D100. Go to RockAuto. That is where I found mine (never thought I would find it). They deal with a company that does nothing but steering boxes.
Yeah, thats my 2nd option. I was hoping to score a used one on the cheap. The cost of come of the MANUAL boxed online seems a bit asinine to me. One place lists them for 600!
I'd pull the one out of my D100 but I believe they are different...