Of course, I have not been searching for Delvac One, but I have never seen it. I expect that the only place you will find it will be at Truck Stops and Mobil wholesale dealers.

In the small farm communities it's easy to find the Petroleum distributors. They sell on a wholesale basis, distribute fuel and lubricants to the dealers(filling stations) and farmers. I expect you can find it there and at a good price.

Good luck,