I'm planning on swapping my scrap pile for a stack of dollar bills come springtime

When I drag that old disc out, I'll check for an ID tag. Highly unlikely it's still legible though. We're talking SEVERE rust here.
Implements are worse than old tractors when it comes to investment required to make new again vs. real world value. Generally, it's easier and cheaper to find another that's intact than to buy all sorts of hard-to-find parts. Last year about this time, when I re-did the #66 Massey plow, I easily spent $1000 by the time I found the plow, got it here, bought all new wear parts, and put a "show car" paint job on it. I've got a great looking $400 plow now......
I just bought a Massey Ferguson #39 2-row corn planter off of EBAY. I paid more than I should have, but it's virtually "like new". I could have bought several "fix-er-uppers" for less money, and then spent a small fortune on parts. Going after it saturday!