Yep, it is a white back. You may remember I was the first member on this topic and I had never seen anything but white backs for this set. I wonder if the gray backs were regional?
I'll post a topic on the BV of the Parrish RC in the Price Check Room and we'll take it from there once we find the value. With some of the wild price fluctuations in older basketball recently I want to double check the current value of this card.