I don’t know the size off the top of my head, but I can tell you that the majority of bearings come in standard sizes. If you measure the outside diameter of the entire bearing, as well as the inside diameter of the shaft hole and the width you will be able to match it up with the correct sizing to order. 6202 sounds like it could be right, but definitely verify the size.
The letters like RS, Z, o ZZ indicate the way the rollers are protected. ZZ means it has metal shields on both sides, Z means it has a metal shield on only one size RS means rubber seal on one side and 2RS means rubber seal on both sides. No letters usually indicates an “open face” bearing which is usually used in an application where the bearing is greased on a maintenance schedule.
You likely want a 2rs bearing so it is totally sealed.