Well, I have a "store brand in disguise" with the second tier thumb latch high arch chassis simply "badged" as Victa on the base with a dress cowl label that says 2 Stroke in large and high arch in smaller print below, along with basic handles and non ball bearing wheels.
There is an important clue with this mower. It came with the label that says cold start primer press once only. I believe that is only used for the LM carburettor with the integrated primer bulb on the face and this mower came with an LM like this. I should know, I have one that I'm doing up at the moment and a neighbour of mine years ago had this exact mower and I recall those features on his. So I think store brands must have been available with the 125 at least well into 1978.