The colours listed in the Canadian section were apparently used in addition to the US colors so your paint may indeed be Brewster Green. Also one of the Canadian service letters (July 1929) mentions that Mandalay Green - a lighter shade of Brewster Green was offered. Perhaps it was carried over into the early 1930 production? I have access to all of the CMAFF documentation but it does not appear that we have actual paint chips.
https://www.cmaff.com/Members_Area/L...0614_img_0.pdf