Very nice pipe! Your example is from as early as 1936, when the line was introduced, to probably no later than 1939-1940. It is possibly that it was made as late as the end of the war, but 'common' knowledge states that very little production occurred during the war years and it is not known exactly when the MADE IN LONDON ENGLAND stamping started exactly. The COMOYS (look close, it is without an apostrophe) is also consistent with this era, postwar era examples were stamped in the singular ROYAL COMOY. I have not yet encountered a ROYAL COMOYS with the MADE IN LONDON ENGLAND COM stamp.
According to Jon Guss, when introduced the line commanded an almost 50% premium over the next highest grade. These pipes were usually straight grain, or very close to it.
The BLUE RIBAND displaced the ROYAL grade fairly quickly, and it is not known if production continued immediately during or after the war. When it did reappear, it carried the singular COMOY stamp and was downgraded, eventually heavily, until it was an entry level pipe by the 1960s. Postwar pipes have no particular collector value.
I cannot wait to see your new acquisition cleaned and polished, it is a real cracker.
I have several at this point in time, they are some of my favorite pipes.
Doc