I wish I'd written down what year I got the couple I had before. For some reason I'm thinking the Reggie/tug is 78 and the Yaz/carew with no color is 79. I moved to town very late in 77, I don't remember if the inserted discs were around then, But I did get a couple, which makes me think the Sears either put them out late or didn't have them till 78. Possible with a big chain, stuff sometimes stayed in the supply line a long time. (And crazier in Canada, I bought 77 OPC in the Canadian half of Glacier park in mid summer 78 and they'd just gottten them)
We played in the backyard which had a semi Polo grounds feel to it - Wall and trees along left field, lillacs along right, narrow and about 100ft to the grapevines along the fence in center. We'd play late into fall, the season ending when the ball hit either the 3rd base rock or the stone wall in left and shattered. Usually a 20degree day in early Dec.
That's part of why I'm thinking the colorless bat sleeves are a different year. We used up a few balls a year, but only wrecked one or two bats.
Steve B