Probably quite common for component makers to supply a part with variances for different clients. It's only a matter of positioning of the holes on the same part, depending on the flywheel that will go onto it. There may be eight mower makers that use this particular piece, with no two precisely the same.
I thought this was a hovering mower until I saw the picture of the regular Flymo branded push mower with wheels!!!


Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!