They were only made from ‘73 to ‘75. With all of the other Marantz offerings at that time, plus all of the other manufacturers offerings, it’s not surprising the manufactured number would be low. I was prime marketing target during those years as I was in my mid 20’s. Almost none of my friends had integrated amps or separates because we simply didn’t have the money. Most young guys went for receivers to get the most bang for the buck. And in those days, i’m betting most of the buyers were young guys.