https://imgur.com/gallery/6C91r

Thanks Doug. I was going to guess 80's but it was just a guess. These are elusive information-wise.Doug D. wrote:These are tough to pin down. I have access to many catalogs and other literature, but haven't found anything among them yet. The only ones I've seen have metric capacity and microwave on them, so that would be mid-1970s at the earliest.
Doug D. wrote: More digging. They appear to have debuted in 1987 with plastic covers as part of the Storage Plus Storage System. They do not appear in 1986 catalogs. 7401, 7402, and 7403 were cataloged as 3, 6, and 10 cup "all purpose bowls", which translates to 1-1/2 pt, 1-1/2 qt, and 2-1/2 qt. Also sold as a #7252 set of three.
They're after 1986, when decorated opal Pyrex was discontinued. Of course, now I need to get some.