MilDiver
847
Julian covered it well, I'll add my 2c.
Papers - its difficult to come by with. I'll not waste time over it. an archive is the way. (500SFR and few weeks).
As a general rule of thumb, unless a watch is described as NOS, and it is proven to be like that, I don't trust professional sellers' description (dealers, auction houses etc), I've learned that most of the time they use wording to highlight the best, ignoring the bad, and remove all legal responsibility from them.
I usually "calculate" a needed service by Patek into the price I'm willing to pay. ~1500-2000$ on avg for a Calatrava by Patek HQ.
Originality above all, and the dial (and hands) are the rarest item to fix / restore. so, on all watches my go/no go is the dial condition.
An amazing journey you got, good luck.