Bart, if this tractor was an export model made in the US it will not have metric bearings. On the other hand any bearing in it will have the bearing manufactuers name and part number of the bearing etched or stamped on the sides of the races somewhere. If you take the bearings off the shafts try do get them off complete, do not torch them off as this would destroy any reference numbers you will find necessary to obtain replacement.
While replacement bearings may have to be special ordered for you I would bet any mid size to large bearing and seal supply company in the Netherlands could use the part numbers to cross over and get them for you in their brand. Take the old bearing in and get the parts counter guys to help you. I would bet bearings are still available, but probably not from Case.
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