hifi engine

Bang & Olufsen CD 50

I have a B&O CD50 which began to give me loading problems and therefore would not play. I tracked the problem down to loading motor belt, part 9126. The belt is too slack and the loading gears don't complete their cycle and close the clamper switch.
Is there a way to restore tension to this belt without changing it? Disassembly of this unit is very complicated!
If I should have to change this belt, does anyone know where I might find one?