Have a look at my Dummy Stamps Newsletter issue 23 to be found via
www.stampprinters.info/dummystamps.htm where I devote a page to the item in question. What I do not do is indicate the date, which is quite remiss of me!
I have the Gibbons Magazine Archive and can reveal that this particular colour guide was first advertised for sale in the December 1923 issue of Gibbons Monthly Journal, but see below. The cover is depicted in the advert and is shown to be identical to that depicted here by REVENUER.
A review in part states that this new edition of 100 labels (the previous had just 45 colours) was "...designed, printed, gummed and perforated by Perkins Bacon & Co Ltd., the famous stamp printers...." This edition was available until around 1940 (presumably undergoing reprints along the way, or they had grossly over-ordered the first batch!)
Gibbons Stamp Monthly of June 1990 has a one-page article all about the colour guides issued by Gibbons (its first was in 1899), stating that they first announced the intended publication of REVENUER's version in June 1922.
Hope this helps.
GLENN MORGAN