Front hub question

A friend of mine has an 08 rzr .over the weekend we were replacing his front wheel bearings. His rzr has two different front hubs.
After some looking around I think one is the upgraded hub while the other is the original.
We have looked around and find hubs listed for an 08 and then find ones listed for a 10-12 model.
Is the 08 the small or older style and the ones shown for the 10-12 models the new style.

basically I need a part number for the upgraded hubs for an 08 rzr