NVSRR
Back in 2010 i was on a bridge rebuild just north of Reading PA. I was very surprised to see a coal delivery to a house using a very modern truck that had the sissirs lift mechanism to lift the body to dump coal.
Jordan made an HO coal truck with that scissors mechanism - an old Mack truck as I recall. Coal trucks tended to last a long time so one could put a somewhat more modern truck front on that model - say 1940s era - and it would have been plausible into the 1960s.
Selling coal for residential and business heating (as opposed to for electricity generation) would of course be seasonal so it stands to reason that coal dealers would do something else - lumber as indicated, but in my recollection, more commonly "ice and coal" companies, many of which probably were making their real money selling fuel oil even as they kept that "ice and coal" name. There were several such "ice and coal" companies in the Milwaukee area into the 1960s.
My dad told me that the customers in the 1920s and 30s had a two-sided cardboard placard for the window - one side indicated you needed ice, the other side indicated you needed coal. The way you turned it indicated how much you needed.
Here in Milwaukee the last big dealer in residential heating coal, Schneider, finally called it quits in, I think, the late 1980s. In the mid 1980s I moved to a quiet and someone old fashioned residential neighborhood and I could tell from taking my nightly walks in the fall and winter that more than a few of my neighbors were unmistakably burning coal in their furnace. From time to time I could also tell that some of those neighbors also had incinerators for garbage - another unmistakable aroma.
It was probably more practical to be a hold out and still have a coal furnace into the 1960s to 1980s than it would have been to have a true icebox instead of a refrigerator.
Dave Nelson