If the bearings are original, they would probably be Delco-Moraine, but I don't know what the flying 'P' would signify. They are not Federal Mogul bearings because the F-M number for the individual bearings is 3191CP for the straight shells and 3192CP for the flanged bearing. In most cases, undersize bearing shells are marked with a size designation, such as .010, .020, etc.
But, like Chris said, you really need to measure the journals to be certain as to what size they are.
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