Well... I'd say he's shooting 4x5 using the ground glass to focus
Film is in a roll film back since you can see the boxes of film on the table.
But the film was released on March 2nd, 1940... which is way after Kodak had first released its roll film holder and the Eastman American Film that went with it...
So I guess he's not using an Eastman camera even if it looks like one.
He's using the Little Giant camera... which I've never heard of.
It also was before credit cards were invented... and he paid at the post office for his package (Cash on Delivery is printed on the crate)