Normally a rebuilt generator is exchanged without the pulley. Different applications use the same generator and different belt widths. I still have a pulley puller laying around somewhere. Pulleys are not that hard to find but you need to know the belt width. I prefer to either fix generators myself, or take them to an old timer who still specializes in starters and generators. Over the counter rebuilts are thrown together by people who know they will never have to look you in the eye and don't really care.