How can I fix my Morphy Richards Food Processor 48480B? ?

My Morphy Richards Food Processor 48480B has worked well for the weveral years I have had it. When I last tried to use it, it didn't work at all. I carefully checked the bowl/main unit connection, the security cap on the blender shaft, etc. I tried to take it apart. the belt wheel cannot be removed because instead of being held down with a screw, it is attached by a rivet to the motor shaft. Under that is the motor itself. I simply can't get to it. And if I were successful at reaching the motor, how do I test it? How much would a new motor cost? Should I try to cut the rivet? Thanks for your help!