You can enter the average value of your near PD and far PD.For your instance, you can enter 64 for your PD when making computer glasses. Actually, 1-2mm difference in PD doesn't affect that much to the accuracy of your glasses.
It doesn't matter if the PD difference is less than 4mm. As computer eyeglasses is for middle vision, I think you can get the average value which is 64. Or you can ask your doctor for more accurate information.