If you are talking about the wheel nuts then they are std car parts or expensive mower parts but you will ned to find a car parts store with an attendant who knows what they heave & where it is.
I took a sample to a nut & bolt shop.
They told me it fitted a Valiant ( locally rebadged Dodge ) and to go to the wreckers around the corner.
Got 4 new ones for $ 5 .
Cub wanted $ 2.45 each US + freight
They told me it fitted a Valiant ( locally rebadged Dodge ) and to go to the wreckers around the corner.