I was able to get some information on Charatan's Extra grading by means of this Russian article: http://brbpipe.ru/wp-content/uploads/2012/06/T-shop_1-2011-12_56-69_3.pdf
Here is the interesting part, roughly translated by Google Translate:
Expressive straight grain, excellent flame grain or already at all an excellent cross cut. In this grade, besides a great figure, there are deviations from the classical forms, following the "flame": billiards or Dublin with a sloping bowl. Pipes Extra cost considerably more expensive than De Luxe (up to 8 pounds in the 20s, up to 12 - in the 30s). Sometimes an old memory or on request supplied with hard case.
So it seems to be a Reuben's era grade.
You can read the first half of the article here: http://brbpipe.ru/wp-content/uploads/2011/11/Charatan.pdf