According to my research, it's a 1774 and was made from 1983 to circa 1988. When you have an opportunity, I'd like to see photos of yours including the ratings on the canister & power head. I recorded that it's a Quiet Kleen, too, but now I'm unsure, because only one ad includes it.I have a tan 1770 something ( can't remember the exact model and too hot to go find it in the garage ) Vactronic with black trim and black attachments that I thought was one of the models sold through K-Mart. One of my best vacuums.
Attached are two November 1983 newspaper ads (the others are just listings with no descriptions): the first is from THE TELEGRAPH and the second is from the ST. JOSEPH NEWS-PRESS for the model-type 1774-A. It was definitely one of Eureka's top-of-the line Power Teams at the time.