I have about 10 pilots and 8 have their Coo on the left leg, the other 2 have it on the right leg. Looking on Ebay, right leg variants are being sold as 'rare'
The right leg markings can be found on Ledy figures but also on Kenner ones too although it's more common for them to be found on the left if they are Kenner as you have noticed (8 out of 10 is pretty common lol)
The 2 you have with markings on the right aren't neccessarily Ledy though, it's just one factor in determining a Ledy figure.