G'day Mowerfreak,
It's not a storebrand - that Impala model is in the 1973 season Victa brochure here:
https://www.outdoorking-forum.com.au/forum/u...ALOGUE_-_Victa_1973_Range.html#Post62024The 1974 and 1975 range brochures show only the Briggs engined 4-stroke version.
At that time, Victa did not yet offer a high arch storebrand model. For example the 'MSAA Craftsman' storebrand catcher model of the time still used the long-lived 'Mayfair' mid-arch base.