Here you go:

The Pyrex themselves: https://smile.amazon.com/Pyrex-3-Cup-Rectangle-Storage-Containers/dp/B00JJILWQ0/ref=sr_1_1?ie=UTF8&qid=1489183027&sr=8-1&keywords=pyrex+3cup

I bought these lids so I could microwave the whole package, plus they seal and look better: https://smile.amazon.com/Pyrex-No-Leak-3-Cup-Rectangle-Storage/dp/B00DSABDSM/ref=sr_1_16?ie=UTF8&qid=1489183131&sr=8-16&keywords=pyrex+3cup+lid

It looks like amazon is out of the lids, but hopefully you can find them somewhere now that you know what they look like!