Wash belt
When I got my A50 I used a cut to length tube type belt I ordered online. I forget the company, but you order the tubing in whatever diameter you need, and however many feet you need, as it is sold by the foot. At the same time, you order a pack of metal grommets, I think they came in packs of 25. When the belt tubing and grommets arrive, simply cut the tubing a little bit shorter than your old belt, and force both open ends into the grommet, which locks in place. Instant custom belt.
I don't know about the spinner belt, as mine was still in great condition, but it appears far heavier, and the cut to length tubing probably wouldn't work for it.