My first instinct is that these hands aren't correct, but since this is a 2913-1 (apparently) I wondered if the earlier versions may have had different hands. Or could they just be broad arrow handset from some other model.
Definitely not Omega. In my opinion broad arrow handsets for Seamaster 300 are all identical... but I am sure the SM300 experts will give their opinion soon 馃榾
Caseback and its inside marking look legit for a -1 compared to known 2913-1 photos. Can you please share a movement photo and the first five digits of the serial number?