Moose Dog said:
Does a damaged tail block sound too risky to you?
Not if the price is right!
My D-44 came to me with a split tailblock and a topcrack. Together, it was <$100 to have them both repaired... glue and a couple cleats on the top crack. Glue and a thin maple(?) overlay on the tailblock.
Here's Frank Ford repairing a tailblock...
Now, the tail split on the D-50 in question is quite a bit more severe than on my D-44 (which was also old enough that cosmetics were not an issue), and one side of the crack is displaced inward. Obviously, this will have to be pushed back out flush. W/O a view inside, can't say if anything else got knocked loose... but I wouldn't be surprised to find it's just the tailblock.
From there, the repair is probably quite similar to what is shown in Ford's website... work some glue into the tailblock split, and add a thin overlay to re-inforce the tailblock. Once done, it is probably stronger than the original tailblock. A good luthier might minimize the visual impact... with some touch up/amalgamation of the NC finish, it might be hard to notice the repair (and how many people look at the tail of your guitar?). But it should be structurally sound, and the repair should have no effect on the tone.
So... if you could get it for a decent price, figuring in the cost of the repair, you might get a great deal on a great sounding D-50.
Dave