Need help on engine case changes from year to year

[CDBiker220]

Hi, I recently had my right crank bearing come loose in the bore on my used 07 EC300 i picked up. Had case sleeved and machined, installed new bearing. Now 4 months later...same thing. It seems the shaft the clutch rides on is bent, and the gear on the clutch basket is pretty loose, must of just hammerd the crank gear enough to wear out the bore in the case (2 times now). So, im not sure if i want to repair the case again. There are some cases on ebay as well as a wanted ad on the site here i posted but Im unsure what years will interchange. There is a 01 xc300 case on ebay and a "02-04" EC300 case. Either of these work? Thanks for any help..this bike is driving me crazy...was a six days bike...must of got beat bad.