To buy ANY bearings, I recommend going to King Bearings in most medium-to-large cities, and take an old bearing with you. They will measure your part, cross-reference it and locate one in their stock. Bearings are made to myriad sizes for international use. They have bearings for Model A's from 120 years ago- I'm sure a mid-'60s car made with off-the-shelf parts will be no problem.
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