You also asked about bearings. Your hubs are ball-bearing hubs, and those sizes have not changed. They are readily available. It is not even hard to repack the hubs with new balls and adjust the hub. Do you know anything about the history of the bike and how much it was ridden? From the single photo, it looks in good shape. If you wanted to replace or up-grade anything on this bike, it should not be hard-at-all, to do. What is the condition of the tires?