Am I reading your post wrong or are you saying they offered two different strainers for this drum from 1934 through the early 40s?Thanks Havard!
Well, I'm by no means any expert on this, but both strainers existed in the thirties, no doubt about that. I have attached images from the 1936 and 1940 catalogue and you can see the two different strainers. The "Eagle emblem" on mine is listed as an option. There is no mention of the different strainers.
One possibility is that mine is a different model from yours. I went through the catalogues again and found out that the "Legion Heir" series was offered with or without "centre supports". All the pictures of these drums have the new strainer, so it might be that my drum actually is a "Legion Heir Parade Drum" without "Centre supports". One more thing to back this up is that mine have a "drum key" holder as well, which also matches the catalogue pictures.
Here's a quote from Rob Cooks Slingerland book about the strainer on your drum:
672 POST STRAINER
"....This strainer was sold on all parade drums in 1928. From 1934 on it was sold only on the lower-priced parade drums. This strainer was discontinued in the early '40's (wartime)"