Rear bearings for a 49cc atv?

I have a 49cc mini atv, and the back bearings that go on the axle broke. Can anybody give me a link to where i can buy new ones for a good price? Here is a link to what it looks like, go to the blue one on the bottom. Its the same exact thing:http://humble.olx.com/49cc-mini-quad-bormotorsports-349-cash-new-with-warranty-iid-78403780