I do not believe this is a double transfer, just inking anomalies
It's the milky blue shade of R13c, similar to the milky blue of R97. I personally think there should be three color listings for R13 in the same manner of R97, but every time I bring it up, there's resistance.
In my opinion the milky blue shade is just as common as the normal blue. It's only the ultramarine (R13e) that is truly scarce.
Here is an image of the 3 R13 color shades scanned together. From left to right:
1. Ultramarine (R13e)
2. Milky blue (R13c)
3. Blue (R13c)