This is a perforated basket washer. Amana never had a solid tub washer, in fact didn't offer a laundry line until the early 80's. While Speed Queen moved to rear opening lids with the change to perforated baskets in their domestic models in 1980, they made the side opening lid for the Amana line, but only for a few years.
I had this same washer for a while, a good machine. Copious amounts of water, recirculating filter and and that slow-stroke agitation that is still cherished.