Just replace the bearings with what were in there. Unless you want to get into trying to figure out preload and all that fun stuff. Then I would go with angular contact bearings since they will be metric. Timken Rollers are standard imperial sizes (Invented in the US) and ball bearings are metric (Invented in europe) so you will have a problem right from the start. There are rollers in metric and vice-versa but the selection is not great.