1938 Nickel: Which Doubled Die Obverse Is This?

Possibly. I have pushed the little inspection scope to its limits. I will need to set up the laptop and real microscope later this evening. That's the only equipment I have that takes adequate photos through the slab.

fantastic DDO Brand.

Alas, I don't think microscope examination has supplied any great insights.

You could say that the profile is doubled. However, I feel that the edge around the bust could just as easily be described as die polishing or die preparation common to the early Jefferson nickels. The layer cake tripling or quadrupling is clearly visible. I would tend to say that the thick blockiness points towards QDO FS-106. The nickel is a late die state strike. Do those scratches between U and S actually match the ones on Brian's Variety Coins? Rather hard to say.

That has some nice splits on the series.
Its a shame it's difficult to attribute.