With that part number they would be original. The other numbers may be extremely faint. Are there any stampings on the inside of the rims? They would show the year stamping. Look for M and a number to the right of that letter. There will be a 9 or 0 or 1 under the M and number. The 9, 0, or 1 indicates the year, 1969, 1970 or 1971. There are a lot of other misc stampings in the same area as the numbers etc that I just described. Let us know what you find, or post a picture or two.