The std wheels for '65 should be 5.5", not 8". The std tire size was 6.70 x 15, 4 ply, 6 ply optional. That is an obsolete size, if you want 100% original, then Coker, Universal, or Lester will be the best choice. If you don't mind not being original, then a 215/75/15 is the modern equivalent to the OE size. I will tell you, that size is starting to become obsolete, too, and you may have to settle for a passenger car tire in that size.
If you do have an 8" wide rim, then you can go with a 235/75/15, which will be taller/wider than OE, but has much better availability and selection of tire types.
Last edited by LONGBOX55; 11/28/2007 9:59 PM. Reason: added more info