> heating oil dealers do have pumps out front and sell it as "off road diesel",

I assume they sell their ORD at the same price as they'd charge to deliver heating oil, looks like $5.40/gallon in S.NH today.

Sites like Gasbuddy do pretty good at keeping their gasoline prices updated, but are often way off on diesel fuel prices. Actual prices today for fully-taxed road diesel start at $5.39/gallon, though you can do better with memberships (e.g. BJs in Nashua is $5.10 for members) and gas cards.