Don’t know if you have this 1940 ad?
(Attachment Link)
Relooking at this ad (I have one now too) and my opinion is that Empire didn't make the "B-44" but was made by Gilbert Electric Motors. I am pretty sure that is what that ad is telling us. Which is why the engine is such a odd duck when compared to the other Empire line (also no Empire/Model stampings).
Heck, the engine that I have could have come from Gilbert Electric Motors as No. 4242 - no way to tell. Either way, I am telling everyone its a Empire B-44 LOL