Also, as described in the link you posted, the movement is referred as 10.5 manual wind movement.
In answer to your question re: So, what I'm trying to find out is when this type of dial was first used (the "Speedking" one). Either this is an all original 1942 bubbleback speedking ... or it's a "Royal" with a replaced dial and hands.
I am almost sure you have a case/movement for a 1940s 2280 bubble back and a later 1950s Oyster Speedking Precision dial..
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