JD 8320 MFWD, JD 6415 MFWD, FEL, and cab, John Deere MFWD 4600, John Deere 4020, John Deere 4430, John Deere 455 mower, Deutz, and Gehl 4610 perkins skidsteer
You might try amazon.com. They have used books now and they will put you on a list of the book you want if it comes in.
if u contact a kubota dealer and give then the model and serial no. they can get u one.make sure u explain what u want, the owners / operators manuel or the service manuel
You maybe better off buying a new manual,for you may end up w/a manual w/torn pages or grease&oil on some key information your seeking.
If you have a friend that owns a B7500 maybe you could have his manual copy at a copy center.