'Every 1-18 I've ever seen has had the square, open type motor. That is a new one to me'.
Kenny, I think this is a early 1-18. Notice the washer base pan is porcelain coated. I recall that only happened for maybe a year or two. That motor looks like a GM 'Delco'. Otherwise, like you've said, they usually had a sealed GE or Emerson motor.
The machine is very "mint" and evidently the seals are intact. The drip trough under the main seal/bearing looks clean. How sweet!