Walk Behind Lawn Mowers

I purchased bearings and bearing supports for my self-propelled Model 5521RS lawn mower. The part no.listed for the support was inappropriate for my model and allowed the shaft to slip out of alignment and ride against the frame causing them to shear off. I now am faced with buying another set of bearings, bearing supports and a new gear box as the shafts are not readily availabe. Repairs are now going to be an additional $120 plus installation time all because Husqvarna does not keep their "authorised service centers" up to date with part numbers.