Hi BB,
I may be able to help you with that sleve you need, I will know tomorrow, I have just removed a Suzuki from an Ariens and it obviously had a Briggs on it previously and it has had a sleve fitted to it so the Briggs drive pulley would fit. I am fitting a GXV Honda to it and if that has a 25mm shaft I won't need the sleve, that is if I can get it off